diff --git a/harness/temporalHelpers.js b/harness/temporalHelpers.js
index 6f2c00e13c..1c3b7227b0 100644
--- a/harness/temporalHelpers.js
+++ b/harness/temporalHelpers.js
@@ -1421,142 +1421,6 @@ var TemporalHelpers = {
     };
   },
 
-  /*
-   * calendarObserver:
-   * A custom calendar that behaves exactly like the ISO 8601 calendar but
-   * tracks calls to any of its methods, and Get/Has operations on its
-   * properties, by appending messages to an array. This is for the purpose of
-   * testing order of operations that are observable from user code.
-   * objectName is used in the log.
-   */
-  calendarObserver(calls, objectName, methodOverrides = {}) {
-    function removeExtraHasPropertyChecks(objectName, calls) {
-      // Inserting the tracking calendar into the return values of methods
-      // that we chain up into the ISO calendar for, causes extra HasProperty
-      // checks, which we observe. This removes them so that we don't leak
-      // implementation details of the helper into the test code.
-      assert.sameValue(calls.pop(), `has ${objectName}.yearOfWeek`);
-      assert.sameValue(calls.pop(), `has ${objectName}.yearMonthFromFields`);
-      assert.sameValue(calls.pop(), `has ${objectName}.year`);
-      assert.sameValue(calls.pop(), `has ${objectName}.weekOfYear`);
-      assert.sameValue(calls.pop(), `has ${objectName}.monthsInYear`);
-      assert.sameValue(calls.pop(), `has ${objectName}.monthDayFromFields`);
-      assert.sameValue(calls.pop(), `has ${objectName}.monthCode`);
-      assert.sameValue(calls.pop(), `has ${objectName}.month`);
-      assert.sameValue(calls.pop(), `has ${objectName}.mergeFields`);
-      assert.sameValue(calls.pop(), `has ${objectName}.inLeapYear`);
-      assert.sameValue(calls.pop(), `has ${objectName}.id`);
-      assert.sameValue(calls.pop(), `has ${objectName}.fields`);
-      assert.sameValue(calls.pop(), `has ${objectName}.daysInYear`);
-      assert.sameValue(calls.pop(), `has ${objectName}.daysInWeek`);
-      assert.sameValue(calls.pop(), `has ${objectName}.daysInMonth`);
-      assert.sameValue(calls.pop(), `has ${objectName}.dayOfYear`);
-      assert.sameValue(calls.pop(), `has ${objectName}.dayOfWeek`);
-      assert.sameValue(calls.pop(), `has ${objectName}.day`);
-      assert.sameValue(calls.pop(), `has ${objectName}.dateUntil`);
-      assert.sameValue(calls.pop(), `has ${objectName}.dateFromFields`);
-      assert.sameValue(calls.pop(), `has ${objectName}.dateAdd`);
-    }
-
-    const iso8601 = new Temporal.Calendar("iso8601");
-    const trackingMethods = {
-      dateFromFields(...args) {
-        calls.push(`call ${objectName}.dateFromFields`);
-        if ('dateFromFields' in methodOverrides) {
-          const value = methodOverrides.dateFromFields;
-          return typeof value === "function" ? value(...args) : value;
-        }
-        const originalResult = iso8601.dateFromFields(...args);
-        // Replace the calendar in the result with the call-tracking calendar
-        const {isoYear, isoMonth, isoDay} = originalResult.getISOFields();
-        const result = new Temporal.PlainDate(isoYear, isoMonth, isoDay, this);
-        removeExtraHasPropertyChecks(objectName, calls);
-        return result;
-      },
-      yearMonthFromFields(...args) {
-        calls.push(`call ${objectName}.yearMonthFromFields`);
-        if ('yearMonthFromFields' in methodOverrides) {
-          const value = methodOverrides.yearMonthFromFields;
-          return typeof value === "function" ? value(...args) : value;
-        }
-        const originalResult = iso8601.yearMonthFromFields(...args);
-        // Replace the calendar in the result with the call-tracking calendar
-        const {isoYear, isoMonth, isoDay} = originalResult.getISOFields();
-        const result = new Temporal.PlainYearMonth(isoYear, isoMonth, this, isoDay);
-        removeExtraHasPropertyChecks(objectName, calls);
-        return result;
-      },
-      monthDayFromFields(...args) {
-        calls.push(`call ${objectName}.monthDayFromFields`);
-        if ('monthDayFromFields' in methodOverrides) {
-          const value = methodOverrides.monthDayFromFields;
-          return typeof value === "function" ? value(...args) : value;
-        }
-        const originalResult = iso8601.monthDayFromFields(...args);
-        // Replace the calendar in the result with the call-tracking calendar
-        const {isoYear, isoMonth, isoDay} = originalResult.getISOFields();
-        const result = new Temporal.PlainMonthDay(isoMonth, isoDay, this, isoYear);
-        removeExtraHasPropertyChecks(objectName, calls);
-        return result;
-      },
-      dateAdd(...args) {
-        calls.push(`call ${objectName}.dateAdd`);
-        if ('dateAdd' in methodOverrides) {
-          const value = methodOverrides.dateAdd;
-          return typeof value === "function" ? value(...args) : value;
-        }
-        const originalResult = iso8601.dateAdd(...args);
-        const {isoYear, isoMonth, isoDay} = originalResult.getISOFields();
-        const result = new Temporal.PlainDate(isoYear, isoMonth, isoDay, this);
-        removeExtraHasPropertyChecks(objectName, calls);
-        return result;
-      },
-      id: "iso8601",
-    };
-    // Automatically generate the other methods that don't need any custom code
-    [
-      "dateUntil",
-      "day",
-      "dayOfWeek",
-      "dayOfYear",
-      "daysInMonth",
-      "daysInWeek",
-      "daysInYear",
-      "era",
-      "eraYear",
-      "fields",
-      "inLeapYear",
-      "mergeFields",
-      "month",
-      "monthCode",
-      "monthsInYear",
-      "toString",
-      "weekOfYear",
-      "year",
-      "yearOfWeek",
-    ].forEach((methodName) => {
-      trackingMethods[methodName] = function (...args) {
-        calls.push(`call ${formatPropertyName(methodName, objectName)}`);
-        if (methodName in methodOverrides) {
-          const value = methodOverrides[methodName];
-          return typeof value === "function" ? value(...args) : value;
-        }
-        return iso8601[methodName](...args);
-      };
-    });
-    return new Proxy(trackingMethods, {
-      get(target, key, receiver) {
-        const result = Reflect.get(target, key, receiver);
-        calls.push(`get ${formatPropertyName(key, objectName)}`);
-        return result;
-      },
-      has(target, key) {
-        calls.push(`has ${formatPropertyName(key, objectName)}`);
-        return Reflect.has(target, key);
-      },
-    });
-  },
-
   /*
    * oneShiftTimeZone(shiftInstant, shiftNanoseconds):
    *
@@ -1633,8 +1497,11 @@ var TemporalHelpers = {
    * and valueOf methods in the same array. This is for the purpose of testing
    * order of operations that are observable from user code. objectName is used
    * in the log.
+   * If skipToPrimitive is given, it must be an array of property keys. Those
+   * properties will not have a TemporalHelpers.toPrimitiveObserver returned,
+   * and instead just be returned directly.
    */
-  propertyBagObserver(calls, propertyBag, objectName) {
+  propertyBagObserver(calls, propertyBag, objectName, skipToPrimitive) {
     return new Proxy(propertyBag, {
       ownKeys(target) {
         calls.push(`ownKeys ${objectName}`);
@@ -1653,47 +1520,10 @@ var TemporalHelpers = {
         if ((result !== null && typeof result === "object") || typeof result === "function") {
           return result;
         }
-        return TemporalHelpers.toPrimitiveObserver(calls, result, `${formatPropertyName(key, objectName)}`);
-      },
-      has(target, key) {
-        calls.push(`has ${formatPropertyName(key, objectName)}`);
-        return Reflect.has(target, key);
-      },
-    });
-  },
-
-  /*
-   * timeZoneObserver:
-   * A custom calendar that behaves exactly like the UTC time zone but tracks
-   * calls to any of its methods, and Get/Has operations on its properties, by
-   * appending messages to an array. This is for the purpose of testing order of
-   * operations that are observable from user code. objectName is used in the
-   * log. methodOverrides is an optional object containing properties with the
-   * same name as Temporal.TimeZone methods. If the property value is a function
-   * it will be called with the proper arguments instead of the UTC method.
-   * Otherwise, the property value will be returned directly.
-   */
-  timeZoneObserver(calls, objectName, methodOverrides = {}) {
-    const utc = new Temporal.TimeZone("UTC");
-    const trackingMethods = {
-      id: "UTC",
-    };
-    // Automatically generate the methods
-    ["getOffsetNanosecondsFor", "getPossibleInstantsFor", "toString"].forEach((methodName) => {
-      trackingMethods[methodName] = function (...args) {
-        calls.push(`call ${formatPropertyName(methodName, objectName)}`);
-        if (methodName in methodOverrides) {
-          const value = methodOverrides[methodName];
-          return typeof value === "function" ? value(...args) : value;
+        if (skipToPrimitive && skipToPrimitive.indexOf(key) >= 0) {
+          return result;
         }
-        return utc[methodName](...args);
-      };
-    });
-    return new Proxy(trackingMethods, {
-      get(target, key, receiver) {
-        const result = Reflect.get(target, key, receiver);
-        calls.push(`get ${formatPropertyName(key, objectName)}`);
-        return result;
+        return TemporalHelpers.toPrimitiveObserver(calls, result, `${formatPropertyName(key, objectName)}`);
       },
       has(target, key) {
         calls.push(`has ${formatPropertyName(key, objectName)}`);
diff --git a/test/built-ins/Temporal/Duration/compare/order-of-operations.js b/test/built-ins/Temporal/Duration/compare/order-of-operations.js
index 1928bda444..7a1c9ac9f4 100644
--- a/test/built-ins/Temporal/Duration/compare/order-of-operations.js
+++ b/test/built-ins/Temporal/Duration/compare/order-of-operations.js
@@ -146,8 +146,8 @@ const plainRelativeTo = TemporalHelpers.propertyBagObserver(actual, {
   month: 5,
   monthCode: "M05",
   day: 2,
-  calendar: TemporalHelpers.calendarObserver(actual, "options.relativeTo.calendar"),
-}, "options.relativeTo");
+  calendar: "iso8601",
+}, "options.relativeTo", ["calendar"]);
 
 function createOptionsObserver(relativeTo = undefined) {
   return TemporalHelpers.propertyBagObserver(actual, { relativeTo }, "options");
@@ -249,9 +249,9 @@ const zonedRelativeTo = TemporalHelpers.propertyBagObserver(actual, {
   microsecond: 654,
   nanosecond: 321,
   offset: "+00:00",
-  calendar: TemporalHelpers.calendarObserver(actual, "options.relativeTo.calendar"),
-  timeZone: TemporalHelpers.timeZoneObserver(actual, "options.relativeTo.timeZone"),
-}, "options.relativeTo");
+  calendar: "iso8601",
+  timeZone: "UTC",
+}, "options.relativeTo", ["calendar", "timeZone"]);
 
 // order of observable operations with zoned relativeTo and without calendar units except days
 Temporal.Duration.compare(
diff --git a/test/built-ins/Temporal/Duration/prototype/round/order-of-operations.js b/test/built-ins/Temporal/Duration/prototype/round/order-of-operations.js
index 47dfd67327..306656758d 100644
--- a/test/built-ins/Temporal/Duration/prototype/round/order-of-operations.js
+++ b/test/built-ins/Temporal/Duration/prototype/round/order-of-operations.js
@@ -112,8 +112,8 @@ const plainRelativeTo = TemporalHelpers.propertyBagObserver(actual, {
   month: 5,
   monthCode: "M05",
   day: 2,
-  calendar: TemporalHelpers.calendarObserver(actual, "options.relativeTo.calendar"),
-}, "options.relativeTo");
+  calendar: "iso8601",
+}, "options.relativeTo", ["calendar"]);
 
 // basic order of observable operations, without rounding:
 instance.round(createOptionsObserver({ relativeTo: plainRelativeTo }));
@@ -315,9 +315,9 @@ const zonedRelativeTo = TemporalHelpers.propertyBagObserver(actual, {
   microsecond: 654,
   nanosecond: 321,
   offset: "+00:00",
-  calendar: TemporalHelpers.calendarObserver(actual, "options.relativeTo.calendar"),
-  timeZone: TemporalHelpers.timeZoneObserver(actual, "options.relativeTo.timeZone"),
-}, "options.relativeTo");
+  calendar: "iso8601",
+  timeZone: "UTC",
+}, "options.relativeTo", ["calendar", "timeZone"]);
 
 // basic order of operations with ZonedDateTime relativeTo:
 instance.round(createOptionsObserver({ relativeTo: zonedRelativeTo }));
diff --git a/test/built-ins/Temporal/Duration/prototype/total/order-of-operations.js b/test/built-ins/Temporal/Duration/prototype/total/order-of-operations.js
index f2393ee742..f4bb5d120b 100644
--- a/test/built-ins/Temporal/Duration/prototype/total/order-of-operations.js
+++ b/test/built-ins/Temporal/Duration/prototype/total/order-of-operations.js
@@ -95,8 +95,8 @@ const plainRelativeTo = TemporalHelpers.propertyBagObserver(actual, {
   month: 5,
   monthCode: "M05",
   day: 2,
-  calendar: TemporalHelpers.calendarObserver(actual, "options.relativeTo.calendar"),
-}, "options.relativeTo");
+  calendar: "iso8601",
+}, "options.relativeTo", ["calendar"]);
 
 // basic order of observable operations, without rounding:
 instance.total(createOptionsObserver({ unit: "nanoseconds", relativeTo: plainRelativeTo }));
@@ -254,9 +254,9 @@ const zonedRelativeTo = TemporalHelpers.propertyBagObserver(actual, {
   microsecond: 654,
   nanosecond: 321,
   offset: "+00:00",
-  calendar: TemporalHelpers.calendarObserver(actual, "options.relativeTo.calendar"),
-  timeZone: TemporalHelpers.timeZoneObserver(actual, "options.relativeTo.timeZone"),
-}, "options.relativeTo");
+  calendar: "iso8601",
+  timeZone: "UTC",
+}, "options.relativeTo", ["calendar", "timeZone"]);
 
 // basic order of observable operations, without rounding:
 instance.total(createOptionsObserver({ unit: "nanoseconds", relativeTo: zonedRelativeTo }));
diff --git a/test/built-ins/Temporal/Instant/prototype/toString/order-of-operations.js b/test/built-ins/Temporal/Instant/prototype/toString/order-of-operations.js
index 238869e55c..9eef8b2ca8 100644
--- a/test/built-ins/Temporal/Instant/prototype/toString/order-of-operations.js
+++ b/test/built-ins/Temporal/Instant/prototype/toString/order-of-operations.js
@@ -34,8 +34,8 @@ instance.toString(
     fractionalSecondDigits: "auto",
     roundingMode: "halfExpand",
     smallestUnit: "millisecond",
-    timeZone: TemporalHelpers.timeZoneObserver(actual, "options.timeZone"),
-  }, "options"),
+    timeZone: "UTC",
+  }, "options", ["timeZone"]),
 );
 assert.compareArray(actual, expected, "order of operations");
 actual.splice(0); // clear
diff --git a/test/built-ins/Temporal/PlainDate/from/order-of-operations.js b/test/built-ins/Temporal/PlainDate/from/order-of-operations.js
index 3f53d09447..1c85479d04 100644
--- a/test/built-ins/Temporal/PlainDate/from/order-of-operations.js
+++ b/test/built-ins/Temporal/PlainDate/from/order-of-operations.js
@@ -58,14 +58,13 @@ const expected = [
 ];
 const actual = [];
 
-const calendar = TemporalHelpers.calendarObserver(actual, "fields.calendar");
 const fields = TemporalHelpers.propertyBagObserver(actual, {
   year: 1.7,
   month: 1.7,
   monthCode: "M01",
   day: 1.7,
-  calendar,
-}, "fields");
+  calendar: "iso8601",
+}, "fields", ["calendar"]);
 
 const options = TemporalHelpers.propertyBagObserver(actual, {
   overflow: "constrain",
diff --git a/test/built-ins/Temporal/PlainDate/prototype/add/order-of-operations.js b/test/built-ins/Temporal/PlainDate/prototype/add/order-of-operations.js
index c1f29fad5c..d2df806807 100644
--- a/test/built-ins/Temporal/PlainDate/prototype/add/order-of-operations.js
+++ b/test/built-ins/Temporal/PlainDate/prototype/add/order-of-operations.js
@@ -50,8 +50,7 @@ const expected = [
 ];
 const actual = [];
 
-const calendar = TemporalHelpers.calendarObserver(actual, "this.calendar");
-const instance = new Temporal.PlainDate(2000, 5, 2, calendar);
+const instance = new Temporal.PlainDate(2000, 5, 2, "iso8601");
 // clear observable operations that occurred during the constructor call
 actual.splice(0);
 
diff --git a/test/built-ins/Temporal/PlainDate/prototype/since/order-of-operations.js b/test/built-ins/Temporal/PlainDate/prototype/since/order-of-operations.js
index 3dcf5f262a..5d78ded207 100644
--- a/test/built-ins/Temporal/PlainDate/prototype/since/order-of-operations.js
+++ b/test/built-ins/Temporal/PlainDate/prototype/since/order-of-operations.js
@@ -75,16 +75,15 @@ const expected = [
 ];
 const actual = [];
 
-const ownCalendar = TemporalHelpers.calendarObserver(actual, "this.calendar");
-const instance = new Temporal.PlainDate(2000, 5, 2, ownCalendar);
+const instance = new Temporal.PlainDate(2000, 5, 2, "iso8601");
 
 const otherDatePropertyBag = TemporalHelpers.propertyBagObserver(actual, {
   year: 2001,
   month: 6,
   monthCode: "M06",
   day: 2,
-  calendar: TemporalHelpers.calendarObserver(actual, "other.calendar"),
-}, "other");
+  calendar: "iso8601",
+}, "other", ["calendar"]);
 
 function createOptionsObserver({ smallestUnit = "days", largestUnit = "auto", roundingMode = "halfExpand", roundingIncrement = 1 } = {}) {
   return TemporalHelpers.propertyBagObserver(actual, {
diff --git a/test/built-ins/Temporal/PlainDate/prototype/subtract/order-of-operations.js b/test/built-ins/Temporal/PlainDate/prototype/subtract/order-of-operations.js
index 317b7b6831..e33a0fdf8f 100644
--- a/test/built-ins/Temporal/PlainDate/prototype/subtract/order-of-operations.js
+++ b/test/built-ins/Temporal/PlainDate/prototype/subtract/order-of-operations.js
@@ -50,10 +50,7 @@ const expected = [
 ];
 const actual = [];
 
-const calendar = TemporalHelpers.calendarObserver(actual, "this.calendar");
-const instance = new Temporal.PlainDate(2000, 5, 2, calendar);
-// clear observable operations that occurred during the constructor call
-actual.splice(0);
+const instance = new Temporal.PlainDate(2000, 5, 2, "iso8601");
 
 const fields = TemporalHelpers.propertyBagObserver(actual, {
   years: 1,
diff --git a/test/built-ins/Temporal/PlainDate/prototype/until/order-of-operations.js b/test/built-ins/Temporal/PlainDate/prototype/until/order-of-operations.js
index 0807b344d8..6061d392f6 100644
--- a/test/built-ins/Temporal/PlainDate/prototype/until/order-of-operations.js
+++ b/test/built-ins/Temporal/PlainDate/prototype/until/order-of-operations.js
@@ -75,16 +75,15 @@ const expected = [
 ];
 const actual = [];
 
-const ownCalendar = TemporalHelpers.calendarObserver(actual, "this.calendar");
-const instance = new Temporal.PlainDate(2000, 5, 2, ownCalendar);
+const instance = new Temporal.PlainDate(2000, 5, 2, "iso8601");
 
 const otherDatePropertyBag = TemporalHelpers.propertyBagObserver(actual, {
   year: 2001,
   month: 6,
   monthCode: "M06",
   day: 2,
-  calendar: TemporalHelpers.calendarObserver(actual, "other.calendar"),
-}, "other");
+  calendar: "iso8601",
+}, "other", ["calendar"]);
 
 function createOptionsObserver({ smallestUnit = "days", largestUnit = "auto", roundingMode = "halfExpand", roundingIncrement = 1 } = {}) {
   return TemporalHelpers.propertyBagObserver(actual, {
diff --git a/test/built-ins/Temporal/PlainDate/prototype/with/order-of-operations.js b/test/built-ins/Temporal/PlainDate/prototype/with/order-of-operations.js
index 1bdc7103a6..65da7f52d2 100644
--- a/test/built-ins/Temporal/PlainDate/prototype/with/order-of-operations.js
+++ b/test/built-ins/Temporal/PlainDate/prototype/with/order-of-operations.js
@@ -56,8 +56,7 @@ const expected = [
 ];
 const actual = [];
 
-const calendar = TemporalHelpers.calendarObserver(actual, "this.calendar");
-const instance = new Temporal.PlainDate(2000, 5, 2, calendar);
+const instance = new Temporal.PlainDate(2000, 5, 2, "iso8601");
 // clear observable operations that occurred during the constructor call
 actual.splice(0);
 
diff --git a/test/built-ins/Temporal/PlainDateTime/from/order-of-operations.js b/test/built-ins/Temporal/PlainDateTime/from/order-of-operations.js
index 1bda6e2171..973fea62d1 100644
--- a/test/built-ins/Temporal/PlainDateTime/from/order-of-operations.js
+++ b/test/built-ins/Temporal/PlainDateTime/from/order-of-operations.js
@@ -92,8 +92,8 @@ const fields = TemporalHelpers.propertyBagObserver(actual, {
   millisecond: 1.7,
   microsecond: 1.7,
   nanosecond: 1.7,
-  calendar: TemporalHelpers.calendarObserver(actual, "fields.calendar"),
-}, "fields");
+  calendar: "iso8601",
+}, "fields", ["calendar"]);
 
 const options = TemporalHelpers.propertyBagObserver(actual, {
   overflow: "constrain",
diff --git a/test/built-ins/Temporal/PlainDateTime/prototype/add/order-of-operations.js b/test/built-ins/Temporal/PlainDateTime/prototype/add/order-of-operations.js
index 5230e93b7b..978a940f9e 100644
--- a/test/built-ins/Temporal/PlainDateTime/prototype/add/order-of-operations.js
+++ b/test/built-ins/Temporal/PlainDateTime/prototype/add/order-of-operations.js
@@ -50,8 +50,7 @@ const expected = [
 ];
 const actual = [];
 
-const calendar = TemporalHelpers.calendarObserver(actual, "this.calendar");
-const instance = new Temporal.PlainDateTime(2000, 5, 2, 12, 34, 56, 987, 654, 321, calendar);
+const instance = new Temporal.PlainDateTime(2000, 5, 2, 12, 34, 56, 987, 654, 321, "iso8601");
 // clear observable operations that occurred during the constructor call
 actual.splice(0);
 
diff --git a/test/built-ins/Temporal/PlainDateTime/prototype/since/order-of-operations.js b/test/built-ins/Temporal/PlainDateTime/prototype/since/order-of-operations.js
index df0236e7cc..c076a0e6fa 100644
--- a/test/built-ins/Temporal/PlainDateTime/prototype/since/order-of-operations.js
+++ b/test/built-ins/Temporal/PlainDateTime/prototype/since/order-of-operations.js
@@ -93,8 +93,7 @@ const expected = [
 ];
 const actual = [];
 
-const ownCalendar = TemporalHelpers.calendarObserver(actual, "this.calendar");
-const instance = new Temporal.PlainDateTime(2000, 5, 2, 12, 34, 56, 987, 654, 321, ownCalendar);
+const instance = new Temporal.PlainDateTime(2000, 5, 2, 12, 34, 56, 987, 654, 321, "iso8601");
 
 const otherDateTimePropertyBag = TemporalHelpers.propertyBagObserver(actual, {
   year: 2001,
@@ -107,8 +106,8 @@ const otherDateTimePropertyBag = TemporalHelpers.propertyBagObserver(actual, {
   millisecond: 250,
   microsecond: 500,
   nanosecond: 750,
-  calendar: TemporalHelpers.calendarObserver(actual, "other.calendar"),
-}, "other");
+  calendar: "iso8601",
+}, "other", ["calendar"]);
 
 function createOptionsObserver({ smallestUnit = "nanoseconds", largestUnit = "auto", roundingMode = "halfExpand", roundingIncrement = 1 } = {}) {
   return TemporalHelpers.propertyBagObserver(actual, {
diff --git a/test/built-ins/Temporal/PlainDateTime/prototype/subtract/order-of-operations.js b/test/built-ins/Temporal/PlainDateTime/prototype/subtract/order-of-operations.js
index d58bbb9edd..34cb0acde0 100644
--- a/test/built-ins/Temporal/PlainDateTime/prototype/subtract/order-of-operations.js
+++ b/test/built-ins/Temporal/PlainDateTime/prototype/subtract/order-of-operations.js
@@ -50,10 +50,7 @@ const expected = [
 ];
 const actual = [];
 
-const calendar = TemporalHelpers.calendarObserver(actual, "this.calendar");
-const instance = new Temporal.PlainDateTime(2000, 5, 2, 12, 34, 56, 987, 654, 321, calendar);
-// clear observable operations that occurred during the constructor call
-actual.splice(0);
+const instance = new Temporal.PlainDateTime(2000, 5, 2, 12, 34, 56, 987, 654, 321, "iso8601");
 
 const fields = TemporalHelpers.propertyBagObserver(actual, {
   years: 1,
diff --git a/test/built-ins/Temporal/PlainDateTime/prototype/toString/order-of-operations.js b/test/built-ins/Temporal/PlainDateTime/prototype/toString/order-of-operations.js
index 231721be90..76f5446f7a 100644
--- a/test/built-ins/Temporal/PlainDateTime/prototype/toString/order-of-operations.js
+++ b/test/built-ins/Temporal/PlainDateTime/prototype/toString/order-of-operations.js
@@ -25,8 +25,7 @@ const expected = [
 ];
 const actual = [];
 
-const calendar = TemporalHelpers.calendarObserver(actual, "this.calendar");
-const instance = new Temporal.PlainDateTime(1990, 11, 3, 15, 54, 37, 123, 456, 789, calendar);
+const instance = new Temporal.PlainDateTime(1990, 11, 3, 15, 54, 37, 123, 456, 789, "iso8601");
 // clear observable operations that occurred during the constructor call
 actual.splice(0);
 
diff --git a/test/built-ins/Temporal/PlainDateTime/prototype/until/order-of-operations.js b/test/built-ins/Temporal/PlainDateTime/prototype/until/order-of-operations.js
index d75480f4cd..de054949f7 100644
--- a/test/built-ins/Temporal/PlainDateTime/prototype/until/order-of-operations.js
+++ b/test/built-ins/Temporal/PlainDateTime/prototype/until/order-of-operations.js
@@ -93,8 +93,7 @@ const expected = [
 ];
 const actual = [];
 
-const ownCalendar = TemporalHelpers.calendarObserver(actual, "this.calendar");
-const instance = new Temporal.PlainDateTime(2000, 5, 2, 12, 34, 56, 987, 654, 321, ownCalendar);
+const instance = new Temporal.PlainDateTime(2000, 5, 2, 12, 34, 56, 987, 654, 321, "iso8601");
 
 const otherDateTimePropertyBag = TemporalHelpers.propertyBagObserver(actual, {
   year: 2001,
@@ -107,8 +106,8 @@ const otherDateTimePropertyBag = TemporalHelpers.propertyBagObserver(actual, {
   millisecond: 250,
   microsecond: 500,
   nanosecond: 750,
-  calendar: TemporalHelpers.calendarObserver(actual, "other.calendar"),
-}, "other");
+  calendar: "iso8601",
+}, "other", ["calendar"]);
 
 function createOptionsObserver({ smallestUnit = "nanoseconds", largestUnit = "auto", roundingMode = "halfExpand", roundingIncrement = 1 } = {}) {
   return TemporalHelpers.propertyBagObserver(actual, {
diff --git a/test/built-ins/Temporal/PlainDateTime/prototype/with/order-of-operations.js b/test/built-ins/Temporal/PlainDateTime/prototype/with/order-of-operations.js
index 7b32ae3888..c7e6b2a6c7 100644
--- a/test/built-ins/Temporal/PlainDateTime/prototype/with/order-of-operations.js
+++ b/test/built-ins/Temporal/PlainDateTime/prototype/with/order-of-operations.js
@@ -73,7 +73,7 @@ const expected = [
 ];
 const actual = [];
 
-const calendar = TemporalHelpers.calendarObserver(actual, "this.calendar");
+const calendar = "iso8601";
 const instance = new Temporal.PlainDateTime(2000, 5, 2, 12, 34, 56, 987, 654, 321, calendar);
 // clear observable operations that occurred during the constructor call
 actual.splice(0);
diff --git a/test/built-ins/Temporal/PlainMonthDay/from/order-of-operations.js b/test/built-ins/Temporal/PlainMonthDay/from/order-of-operations.js
index 745a378bb5..9c7b01073f 100644
--- a/test/built-ins/Temporal/PlainMonthDay/from/order-of-operations.js
+++ b/test/built-ins/Temporal/PlainMonthDay/from/order-of-operations.js
@@ -68,8 +68,8 @@ const fields = TemporalHelpers.propertyBagObserver(actual, {
   month: 1.7,
   monthCode: "M01",
   day: 1.7,
-  calendar: TemporalHelpers.calendarObserver(actual, "fields.calendar"),
-}, "fields");
+  calendar: "iso8601",
+}, "fields", ["calendar"]);
 
 const options = TemporalHelpers.propertyBagObserver(actual, {
   overflow: "constrain",
diff --git a/test/built-ins/Temporal/PlainMonthDay/prototype/toString/order-of-operations.js b/test/built-ins/Temporal/PlainMonthDay/prototype/toString/order-of-operations.js
index 6bd221d57d..36819f6838 100644
--- a/test/built-ins/Temporal/PlainMonthDay/prototype/toString/order-of-operations.js
+++ b/test/built-ins/Temporal/PlainMonthDay/prototype/toString/order-of-operations.js
@@ -16,10 +16,7 @@ const expected = [
 ];
 const actual = [];
 
-const calendar = TemporalHelpers.calendarObserver(actual, "this.calendar");
-const instance = new Temporal.PlainMonthDay(5, 2, calendar);
-// clear observable operations that occurred during the constructor call
-actual.splice(0);
+const instance = new Temporal.PlainMonthDay(5, 2, "iso8601");
 
 const options = TemporalHelpers.propertyBagObserver(actual, {
   calendarName: "auto",
diff --git a/test/built-ins/Temporal/PlainMonthDay/prototype/with/order-of-operations.js b/test/built-ins/Temporal/PlainMonthDay/prototype/with/order-of-operations.js
index 1fa2996016..d01ce31c21 100644
--- a/test/built-ins/Temporal/PlainMonthDay/prototype/with/order-of-operations.js
+++ b/test/built-ins/Temporal/PlainMonthDay/prototype/with/order-of-operations.js
@@ -52,10 +52,7 @@ const expected = [
 ];
 const actual = [];
 
-const calendar = TemporalHelpers.calendarObserver(actual, "this.calendar");
-const instance = new Temporal.PlainMonthDay(5, 2, calendar);
-// clear observable operations that occurred during the constructor call
-actual.splice(0);
+const instance = new Temporal.PlainMonthDay(5, 2, "iso8601");
 
 const fields = TemporalHelpers.propertyBagObserver(actual, {
   year: 1.7,
diff --git a/test/built-ins/Temporal/PlainTime/prototype/since/order-of-operations.js b/test/built-ins/Temporal/PlainTime/prototype/since/order-of-operations.js
index c2cf9614bf..2397853675 100644
--- a/test/built-ins/Temporal/PlainTime/prototype/since/order-of-operations.js
+++ b/test/built-ins/Temporal/PlainTime/prototype/since/order-of-operations.js
@@ -62,7 +62,7 @@ const other = TemporalHelpers.propertyBagObserver(actual, {
   microsecond: 1.7,
   nanosecond: 1.7,
   calendar: "iso8601",
-}, "other");
+}, "other", ["calendar"]);
 
 const options = TemporalHelpers.propertyBagObserver(actual, {
   roundingIncrement: 1,
diff --git a/test/built-ins/Temporal/PlainTime/prototype/until/order-of-operations.js b/test/built-ins/Temporal/PlainTime/prototype/until/order-of-operations.js
index 3c62047a1e..76f5670cc0 100644
--- a/test/built-ins/Temporal/PlainTime/prototype/until/order-of-operations.js
+++ b/test/built-ins/Temporal/PlainTime/prototype/until/order-of-operations.js
@@ -62,7 +62,7 @@ const other = TemporalHelpers.propertyBagObserver(actual, {
   microsecond: 1.7,
   nanosecond: 1.7,
   calendar: "iso8601",
-}, "other");
+}, "other", ["calendar"]);
 
 const options = TemporalHelpers.propertyBagObserver(actual, {
   roundingIncrement: 1,
diff --git a/test/built-ins/Temporal/PlainYearMonth/from/order-of-operations.js b/test/built-ins/Temporal/PlainYearMonth/from/order-of-operations.js
index 2c875417e8..df023ba824 100644
--- a/test/built-ins/Temporal/PlainYearMonth/from/order-of-operations.js
+++ b/test/built-ins/Temporal/PlainYearMonth/from/order-of-operations.js
@@ -65,8 +65,8 @@ const fields = TemporalHelpers.propertyBagObserver(actual, {
   year: 1.7,
   month: 1.7,
   monthCode: "M01",
-  calendar: TemporalHelpers.calendarObserver(actual, "fields.calendar"),
-}, "fields");
+  calendar: "iso8601",
+}, "fields", ["calendar"]);
 
 const options = TemporalHelpers.propertyBagObserver(actual, {
   overflow: "constrain",
diff --git a/test/built-ins/Temporal/PlainYearMonth/prototype/add/order-of-operations.js b/test/built-ins/Temporal/PlainYearMonth/prototype/add/order-of-operations.js
index 00d50ea89f..d7f3e65ba8 100644
--- a/test/built-ins/Temporal/PlainYearMonth/prototype/add/order-of-operations.js
+++ b/test/built-ins/Temporal/PlainYearMonth/prototype/add/order-of-operations.js
@@ -78,10 +78,7 @@ const expected = [
 ];
 const actual = [];
 
-const calendar = TemporalHelpers.calendarObserver(actual, "this.calendar");
-const instance = new Temporal.PlainYearMonth(2000, 5, calendar);
-// clear observable operations that occurred during the constructor call
-actual.splice(0);
+const instance = new Temporal.PlainYearMonth(2000, 5);
 
 const fields = TemporalHelpers.propertyBagObserver(actual, {
   years: 1,
diff --git a/test/built-ins/Temporal/PlainYearMonth/prototype/since/order-of-operations.js b/test/built-ins/Temporal/PlainYearMonth/prototype/since/order-of-operations.js
index 1ffc7cc9ae..8799ab6c44 100644
--- a/test/built-ins/Temporal/PlainYearMonth/prototype/since/order-of-operations.js
+++ b/test/built-ins/Temporal/PlainYearMonth/prototype/since/order-of-operations.js
@@ -96,15 +96,14 @@ const expected = expectedMinimal.concat([
 ]);
 const actual = [];
 
-const ownCalendar = TemporalHelpers.calendarObserver(actual, "this.calendar");
-const instance = new Temporal.PlainYearMonth(2000, 5, ownCalendar, 1);
+const instance = new Temporal.PlainYearMonth(2000, 5, "iso8601", 1);
 
 const otherYearMonthPropertyBag = TemporalHelpers.propertyBagObserver(actual, {
   year: 2001,
   month: 6,
   monthCode: "M06",
-  calendar: TemporalHelpers.calendarObserver(actual, "other.calendar"),
-}, "other");
+  calendar: "iso8601",
+}, "other", ["calendar"]);
 
 function createOptionsObserver({ smallestUnit = "months", largestUnit = "auto", roundingMode = "halfExpand", roundingIncrement = 1 } = {}) {
   return TemporalHelpers.propertyBagObserver(actual, {
diff --git a/test/built-ins/Temporal/PlainYearMonth/prototype/subtract/order-of-operations.js b/test/built-ins/Temporal/PlainYearMonth/prototype/subtract/order-of-operations.js
index e1138a853d..ea8caa0933 100644
--- a/test/built-ins/Temporal/PlainYearMonth/prototype/subtract/order-of-operations.js
+++ b/test/built-ins/Temporal/PlainYearMonth/prototype/subtract/order-of-operations.js
@@ -81,10 +81,7 @@ const expected = [
 ];
 const actual = [];
 
-const calendar = TemporalHelpers.calendarObserver(actual, "this.calendar");
-const instance = new Temporal.PlainYearMonth(2000, 5, calendar);
-// clear observable operations that occurred during the constructor call
-actual.splice(0);
+const instance = new Temporal.PlainYearMonth(2000, 5, "iso8601");
 
 const fields = TemporalHelpers.propertyBagObserver(actual, {
   years: 1,
diff --git a/test/built-ins/Temporal/PlainYearMonth/prototype/toString/order-of-operations.js b/test/built-ins/Temporal/PlainYearMonth/prototype/toString/order-of-operations.js
index 95bcf3ff94..dfcdb76f89 100644
--- a/test/built-ins/Temporal/PlainYearMonth/prototype/toString/order-of-operations.js
+++ b/test/built-ins/Temporal/PlainYearMonth/prototype/toString/order-of-operations.js
@@ -16,10 +16,7 @@ const expected = [
 ];
 const actual = [];
 
-const calendar = TemporalHelpers.calendarObserver(actual, "this.calendar");
-const instance = new Temporal.PlainYearMonth(2000, 5, calendar);
-// clear observable operations that occurred during the constructor call
-actual.splice(0);
+const instance = new Temporal.PlainYearMonth(2000, 5);
 
 const options = TemporalHelpers.propertyBagObserver(actual, {
   calendarName: "auto",
diff --git a/test/built-ins/Temporal/PlainYearMonth/prototype/until/order-of-operations.js b/test/built-ins/Temporal/PlainYearMonth/prototype/until/order-of-operations.js
index a3d8084584..c7fa8d06df 100644
--- a/test/built-ins/Temporal/PlainYearMonth/prototype/until/order-of-operations.js
+++ b/test/built-ins/Temporal/PlainYearMonth/prototype/until/order-of-operations.js
@@ -96,15 +96,14 @@ const expected = expectedMinimal.concat([
 ]);
 const actual = [];
 
-const ownCalendar = TemporalHelpers.calendarObserver(actual, "this.calendar");
-const instance = new Temporal.PlainYearMonth(2000, 5, ownCalendar, 1);
+const instance = new Temporal.PlainYearMonth(2000, 5, "iso8601", 1);
 
 const otherYearMonthPropertyBag = TemporalHelpers.propertyBagObserver(actual, {
   year: 2001,
   month: 6,
   monthCode: "M06",
-  calendar: TemporalHelpers.calendarObserver(actual, "other.calendar"),
-}, "other");
+  calendar: "iso8601"
+}, "other", ["calendar"]);
 
 function createOptionsObserver({ smallestUnit = "months", largestUnit = "auto", roundingMode = "halfExpand", roundingIncrement = 1 } = {}) {
   return TemporalHelpers.propertyBagObserver(actual, {
diff --git a/test/built-ins/Temporal/PlainYearMonth/prototype/with/order-of-operations.js b/test/built-ins/Temporal/PlainYearMonth/prototype/with/order-of-operations.js
index d3fb7ece3d..33a9914715 100644
--- a/test/built-ins/Temporal/PlainYearMonth/prototype/with/order-of-operations.js
+++ b/test/built-ins/Temporal/PlainYearMonth/prototype/with/order-of-operations.js
@@ -51,10 +51,7 @@ const expected = [
 ];
 const actual = [];
 
-const calendar = TemporalHelpers.calendarObserver(actual, "this.calendar");
-const instance = new Temporal.PlainYearMonth(2000, 5, calendar);
-// clear observable operations that occurred during the constructor call
-actual.splice(0);
+const instance = new Temporal.PlainYearMonth(2000, 5);
 
 const fields = TemporalHelpers.propertyBagObserver(actual, {
   year: 1.7,
diff --git a/test/built-ins/Temporal/ZonedDateTime/compare/order-of-operations.js b/test/built-ins/Temporal/ZonedDateTime/compare/order-of-operations.js
index 1659432e9a..fc19a1055c 100644
--- a/test/built-ins/Temporal/ZonedDateTime/compare/order-of-operations.js
+++ b/test/built-ins/Temporal/ZonedDateTime/compare/order-of-operations.js
@@ -165,9 +165,9 @@ const one = TemporalHelpers.propertyBagObserver(actual, {
   microsecond: 654,
   nanosecond: 321,
   offset: "+00:00",
-  calendar: TemporalHelpers.calendarObserver(actual, "one.calendar"),
-  timeZone: TemporalHelpers.timeZoneObserver(actual, "one.timeZone"),
-}, "one");
+  calendar: "iso8601",
+  timeZone: "UTC",
+}, "one", ["calendar", "timeZone"]);
 
 const two = TemporalHelpers.propertyBagObserver(actual, {
   year: 2014,
@@ -181,9 +181,9 @@ const two = TemporalHelpers.propertyBagObserver(actual, {
   microsecond: 456,
   nanosecond: 789,
   offset: "+00:00",
-  calendar: TemporalHelpers.calendarObserver(actual, "two.calendar"),
-  timeZone: TemporalHelpers.timeZoneObserver(actual, "two.timeZone"),
-}, "two");
+  calendar: "iso8601",
+  timeZone: "UTC",
+}, "two", ["calendar", "timeZone"]);
 
 Temporal.ZonedDateTime.compare(one, two);
 assert.compareArray(actual, expected, "order of operations");
diff --git a/test/built-ins/Temporal/ZonedDateTime/from/order-of-operations.js b/test/built-ins/Temporal/ZonedDateTime/from/order-of-operations.js
index 53f55522b5..e82e491dba 100644
--- a/test/built-ins/Temporal/ZonedDateTime/from/order-of-operations.js
+++ b/test/built-ins/Temporal/ZonedDateTime/from/order-of-operations.js
@@ -112,9 +112,9 @@ const from = TemporalHelpers.propertyBagObserver(actual, {
   microsecond: 654,
   nanosecond: 321,
   offset: "+00:00",
-  calendar: TemporalHelpers.calendarObserver(actual, "item.calendar"),
-  timeZone: TemporalHelpers.timeZoneObserver(actual, "item.timeZone"),
-}, "item");
+  calendar: "iso8601",
+  timeZone: "UTC",
+}, "item", ["calendar", "timeZone"]);
 
 function createOptionsObserver({ overflow = "constrain", disambiguation = "compatible", offset = "reject" } = {}) {
   return TemporalHelpers.propertyBagObserver(actual, {
diff --git a/test/built-ins/Temporal/ZonedDateTime/prototype/add/order-of-operations.js b/test/built-ins/Temporal/ZonedDateTime/prototype/add/order-of-operations.js
index b8eed6bb38..e8fa4d55f2 100644
--- a/test/built-ins/Temporal/ZonedDateTime/prototype/add/order-of-operations.js
+++ b/test/built-ins/Temporal/ZonedDateTime/prototype/add/order-of-operations.js
@@ -56,11 +56,7 @@ const expected = [
 ];
 const actual = [];
 
-const timeZone = TemporalHelpers.timeZoneObserver(actual, "this.timeZone");
-const calendar = TemporalHelpers.calendarObserver(actual, "this.calendar");
-const instance = new Temporal.ZonedDateTime(0n, timeZone, calendar);
-// clear observable operations that occurred during the constructor call
-actual.splice(0);
+const instance = new Temporal.ZonedDateTime(0n, "UTC");
 
 const duration = TemporalHelpers.propertyBagObserver(actual, {
   years: 1,
diff --git a/test/built-ins/Temporal/ZonedDateTime/prototype/equals/order-of-operations.js b/test/built-ins/Temporal/ZonedDateTime/prototype/equals/order-of-operations.js
index 04847b5b45..c6d65698cf 100644
--- a/test/built-ins/Temporal/ZonedDateTime/prototype/equals/order-of-operations.js
+++ b/test/built-ins/Temporal/ZonedDateTime/prototype/equals/order-of-operations.js
@@ -101,18 +101,11 @@ const other = TemporalHelpers.propertyBagObserver(actual, {
   microsecond: 654,
   nanosecond: 321,
   offset: "+00:00",
-  calendar: TemporalHelpers.calendarObserver(actual, "other.calendar"),
-  timeZone: TemporalHelpers.timeZoneObserver(actual, "other.timeZone"),
-}, "other");
+  calendar: "iso8601",
+  timeZone: "UTC",
+}, "other", ["calendar", "timeZone"]);
 
-const instance = new Temporal.ZonedDateTime(
-  988786472_987_654_321n,  /* 2001-05-02T06:54:32.987654321Z */
-  TemporalHelpers.timeZoneObserver(actual, "this.timeZone"),
-  TemporalHelpers.calendarObserver(actual, "this.calendar"),
-);
-// clear any observable operations that happen due to time zone or calendar
-// calls on the constructor
-actual.splice(0);
+const instance = new Temporal.ZonedDateTime(988786472_987_654_321n,  /* 2001-05-02T06:54:32.987654321Z */ "UTC");
 
 instance.equals(other);
 assert.compareArray(actual, expected, "order of operations");
diff --git a/test/built-ins/Temporal/ZonedDateTime/prototype/since/order-of-operations.js b/test/built-ins/Temporal/ZonedDateTime/prototype/since/order-of-operations.js
index e9552231bc..a4c47635e7 100644
--- a/test/built-ins/Temporal/ZonedDateTime/prototype/since/order-of-operations.js
+++ b/test/built-ins/Temporal/ZonedDateTime/prototype/since/order-of-operations.js
@@ -104,8 +104,6 @@ const expected = [
 ];
 const actual = [];
 
-const ownTimeZone = TemporalHelpers.timeZoneObserver(actual, "this.timeZone");
-const ownCalendar = TemporalHelpers.calendarObserver(actual, "this.calendar");
 const instance = new Temporal.ZonedDateTime(1_000_000_000_000_000_000n, ownTimeZone, ownCalendar);
 
 const dstTimeZone = TemporalHelpers.springForwardFallBackTimeZone();
@@ -132,9 +130,9 @@ const otherDateTimePropertyBag = TemporalHelpers.propertyBagObserver(actual, {
   microsecond: 500,
   nanosecond: 750,
   offset: "+00:00",
-  calendar: TemporalHelpers.calendarObserver(actual, "other.calendar"),
-  timeZone: TemporalHelpers.timeZoneObserver(actual, "other.timeZone"),
-}, "other");
+  calendar: "iso8601",
+  timeZone: "UTC",
+}, "other", ["calendar", "timeZone"]);
 
 function createOptionsObserver({ smallestUnit = "nanoseconds", largestUnit = "auto", roundingMode = "halfExpand", roundingIncrement = 1 } = {}) {
   return TemporalHelpers.propertyBagObserver(actual, {
diff --git a/test/built-ins/Temporal/ZonedDateTime/prototype/subtract/order-of-operations.js b/test/built-ins/Temporal/ZonedDateTime/prototype/subtract/order-of-operations.js
index e9be6a8516..a5aabf8570 100644
--- a/test/built-ins/Temporal/ZonedDateTime/prototype/subtract/order-of-operations.js
+++ b/test/built-ins/Temporal/ZonedDateTime/prototype/subtract/order-of-operations.js
@@ -56,11 +56,7 @@ const expected = [
 ];
 const actual = [];
 
-const timeZone = TemporalHelpers.timeZoneObserver(actual, "this.timeZone");
-const calendar = TemporalHelpers.calendarObserver(actual, "this.calendar");
-const instance = new Temporal.ZonedDateTime(0n, timeZone, calendar);
-// clear observable operations that occurred during the constructor call
-actual.splice(0);
+const instance = new Temporal.ZonedDateTime(0n, "UTC", "iso8601");
 
 const duration = TemporalHelpers.propertyBagObserver(actual, {
   years: 1,
diff --git a/test/built-ins/Temporal/ZonedDateTime/prototype/toString/order-of-operations.js b/test/built-ins/Temporal/ZonedDateTime/prototype/toString/order-of-operations.js
index 48c4fa95a8..fff53abf3f 100644
--- a/test/built-ins/Temporal/ZonedDateTime/prototype/toString/order-of-operations.js
+++ b/test/built-ins/Temporal/ZonedDateTime/prototype/toString/order-of-operations.js
@@ -34,11 +34,7 @@ const expected = [
 ];
 const actual = [];
 
-const timeZone = TemporalHelpers.timeZoneObserver(actual, "this.timeZone");
-const calendar = TemporalHelpers.calendarObserver(actual, "this.calendar");
-const instance = new Temporal.ZonedDateTime(0n, timeZone, calendar);
-// clear observable operations that occurred during the constructor call
-actual.splice(0);
+const instance = new Temporal.ZonedDateTime(0n, "UTC");
 
 instance.toString(
   TemporalHelpers.propertyBagObserver(actual, {
diff --git a/test/built-ins/Temporal/ZonedDateTime/prototype/until/order-of-operations.js b/test/built-ins/Temporal/ZonedDateTime/prototype/until/order-of-operations.js
index db70d40485..fed80a80ac 100644
--- a/test/built-ins/Temporal/ZonedDateTime/prototype/until/order-of-operations.js
+++ b/test/built-ins/Temporal/ZonedDateTime/prototype/until/order-of-operations.js
@@ -132,9 +132,9 @@ const otherDateTimePropertyBag = TemporalHelpers.propertyBagObserver(actual, {
   microsecond: 500,
   nanosecond: 750,
   offset: "+00:00",
-  calendar: TemporalHelpers.calendarObserver(actual, "other.calendar"),
-  timeZone: TemporalHelpers.timeZoneObserver(actual, "other.timeZone"),
-}, "other");
+  calendar: "iso8601",
+  timeZone: "UTC",
+}, "other", ["calendar", "timeZone"]);
 
 function createOptionsObserver({ smallestUnit = "nanoseconds", largestUnit = "auto", roundingMode = "halfExpand", roundingIncrement = 1 } = {}) {
   return TemporalHelpers.propertyBagObserver(actual, {
diff --git a/test/built-ins/Temporal/ZonedDateTime/prototype/with/order-of-operations.js b/test/built-ins/Temporal/ZonedDateTime/prototype/with/order-of-operations.js
index ea2f9178e3..488f10454f 100644
--- a/test/built-ins/Temporal/ZonedDateTime/prototype/with/order-of-operations.js
+++ b/test/built-ins/Temporal/ZonedDateTime/prototype/with/order-of-operations.js
@@ -92,11 +92,7 @@ const expected = [
 ];
 const actual = [];
 
-const timeZone = TemporalHelpers.timeZoneObserver(actual, "this.timeZone");
-const calendar = TemporalHelpers.calendarObserver(actual, "this.calendar");
-const instance = new Temporal.ZonedDateTime(0n, timeZone, calendar);
-// clear observable operations that occurred during the constructor call
-actual.splice(0);
+const instance = new Temporal.ZonedDateTime(0n, "UTC");
 
 const fields = TemporalHelpers.propertyBagObserver(actual, {
   year: 1.7,