diff --git a/test/built-ins/Temporal/PlainDateTime/prototype/withPlainDate/argument-plaindate-calendar-noniso.js b/test/built-ins/Temporal/PlainDateTime/prototype/withPlainDate/argument-plaindate-calendar-noniso.js
index 118282b48d..326aed7c76 100644
--- a/test/built-ins/Temporal/PlainDateTime/prototype/withPlainDate/argument-plaindate-calendar-noniso.js
+++ b/test/built-ins/Temporal/PlainDateTime/prototype/withPlainDate/argument-plaindate-calendar-noniso.js
@@ -10,8 +10,6 @@ includes: [temporalHelpers.js]
 
 const cal = {
   id: 'thisisnotiso',
-  era() { return "the era"; },
-  eraYear() { return 1909; },
   toString() { return "this is a string"; },
   year() { return 2008; },
   month() { return 9; },
@@ -26,9 +24,8 @@ const shifted = pdt.withPlainDate(pd);
 TemporalHelpers.assertPlainDateTime(
   shifted,
   2008, 9, "M09", 6, 3, 24, 30, 0, 0, 0,
-  "calendar is changed if receiver has ISO calendar (1)",
-  "the era",
-  1909
+  "calendar is changed if receiver has ISO calendar (1)"
+  // Testing of era and eraYear should only be coded under intl402
 );
 
 assert.sameValue(
diff --git a/test/built-ins/Temporal/PlainDateTime/prototype/withPlainDate/argument-plaindate-calendar-same-id.js b/test/built-ins/Temporal/PlainDateTime/prototype/withPlainDate/argument-plaindate-calendar-same-id.js
index 2849905981..5c7536640b 100644
--- a/test/built-ins/Temporal/PlainDateTime/prototype/withPlainDate/argument-plaindate-calendar-same-id.js
+++ b/test/built-ins/Temporal/PlainDateTime/prototype/withPlainDate/argument-plaindate-calendar-same-id.js
@@ -13,8 +13,6 @@ const cal1 = {
 };
 const cal2 = {
   id: 'thisisnotiso',
-  era() { return "the era"; },
-  eraYear() { return 1909; },
   toString() { return "this is a string"; },
   year() { return 2008; },
   month() { return 9; },
@@ -28,9 +26,8 @@ const shifted = pdt.withPlainDate(pd);
 TemporalHelpers.assertPlainDateTime(
   shifted,
   2008, 9, "M09", 6, 3, 24, 30, 0, 0, 0,
-  "calendar is changed with same id (1)",
-  "the era",
-  1909
+  "calendar is changed with same id (1)"
+  // Testing of era and eraYear should only be coded under intl402
 );
 
 assert.sameValue(
diff --git a/test/built-ins/Temporal/PlainDateTime/prototype/withPlainDate/argument-plaindate-calendar-same-object.js b/test/built-ins/Temporal/PlainDateTime/prototype/withPlainDate/argument-plaindate-calendar-same-object.js
index f963a3b61d..9eaba18a94 100644
--- a/test/built-ins/Temporal/PlainDateTime/prototype/withPlainDate/argument-plaindate-calendar-same-object.js
+++ b/test/built-ins/Temporal/PlainDateTime/prototype/withPlainDate/argument-plaindate-calendar-same-object.js
@@ -11,8 +11,6 @@ includes: [temporalHelpers.js]
 let calls = 0;
 const cal = {
   id: 'thisisnotiso',
-  era() { return "the era"; },
-  eraYear() { return 1909; },
   toString() {
     ++calls;
     return "this is a string";
@@ -29,9 +27,8 @@ const shifted = pdt.withPlainDate(pd);
 TemporalHelpers.assertPlainDateTime(
   shifted,
   2008, 9, "M09", 6, 3, 24, 30, 0, 0, 0,
-  "calendar is unchanged with same calendars (1)",
-  "the era",
-  1909
+  "calendar is unchanged with same calendars (1)"
+  // Testing of era and eraYear should only be coded under intl402
 );
 
 assert.sameValue(
diff --git a/test/built-ins/Temporal/PlainDateTime/prototype/withPlainDate/argument-plaindate-calendar.js b/test/built-ins/Temporal/PlainDateTime/prototype/withPlainDate/argument-plaindate-calendar.js
index ad9f56f7bb..12a28cb78e 100644
--- a/test/built-ins/Temporal/PlainDateTime/prototype/withPlainDate/argument-plaindate-calendar.js
+++ b/test/built-ins/Temporal/PlainDateTime/prototype/withPlainDate/argument-plaindate-calendar.js
@@ -10,8 +10,6 @@ includes: [temporalHelpers.js]
 
 const cal = {
   id: 'thisisnotiso',
-  era() { return "the era"; },
-  eraYear() { return 1909; },
   toString() { return "this is a string"; },
   year() { return 2008; },
   month() { return 9; },
@@ -26,9 +24,8 @@ const shifted = pdt.withPlainDate(pd);
 TemporalHelpers.assertPlainDateTime(
   shifted,
   2008, 9, "M09", 6, 3, 24, 30, 0, 0, 0,
-  "calendar is unchanged if input has ISO calendar (1)",
-  "the era",
-  1909
+  "calendar is unchanged if input has ISO calendar (1)"
+  // Testing of era and eraYear should only be coded under intl402
 );
 
 assert.sameValue(
diff --git a/test/built-ins/Temporal/PlainDateTime/prototype/withPlainDate/argument-string-iso-calendar.js b/test/built-ins/Temporal/PlainDateTime/prototype/withPlainDate/argument-string-iso-calendar.js
index d86925d1b8..f587118608 100644
--- a/test/built-ins/Temporal/PlainDateTime/prototype/withPlainDate/argument-string-iso-calendar.js
+++ b/test/built-ins/Temporal/PlainDateTime/prototype/withPlainDate/argument-string-iso-calendar.js
@@ -10,8 +10,6 @@ includes: [temporalHelpers.js]
 
 const cal = {
   id: "thisisnotiso",
-  era() { return "the era"; },
-  eraYear() { return 1909; },
   toString() { return "this is a string"; },
   year() { return 2008; },
   month() { return 9; },
@@ -24,9 +22,8 @@ const shifted = dt.withPlainDate("2010-11-12");
 TemporalHelpers.assertPlainDateTime(
   shifted,
   2008, 9, "M09", 6, 3, 24, 30, 0, 0, 0,
-  "calendar is unchanged if input has ISO calendar (1)",
-  "the era",
-  1909
+  "calendar is unchanged if input has ISO calendar (1)"
+  // Testing of era and eraYear should only be coded under intl402
 );
 
 assert.sameValue(
diff --git a/test/intl402/Temporal/PlainDateTime/prototype/withPlainDate/argument-plaindate-calendar-noniso.js b/test/intl402/Temporal/PlainDateTime/prototype/withPlainDate/argument-plaindate-calendar-noniso.js
new file mode 100644
index 0000000000..118282b48d
--- /dev/null
+++ b/test/intl402/Temporal/PlainDateTime/prototype/withPlainDate/argument-plaindate-calendar-noniso.js
@@ -0,0 +1,38 @@
+// Copyright (C) 2022 Igalia, S.L. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-temporal.plaindatetime.prototype.withplaindate
+description: PlainDate calendar is preserved with ISO PDT
+features: [Temporal]
+includes: [temporalHelpers.js]
+---*/
+
+const cal = {
+  id: 'thisisnotiso',
+  era() { return "the era"; },
+  eraYear() { return 1909; },
+  toString() { return "this is a string"; },
+  year() { return 2008; },
+  month() { return 9; },
+  monthCode() { return "M09"; },
+  day() { return 6; }
+};
+const pdt = new Temporal.PlainDateTime(1995, 12, 7, 3, 24, 30, 0, 0, 0);
+assert.sameValue(pdt.calendar.toString(), "iso8601", "PlainDateTime with ISO calendar");
+const pd = new Temporal.PlainDate(2010, 11, 12, cal);
+const shifted = pdt.withPlainDate(pd);
+
+TemporalHelpers.assertPlainDateTime(
+  shifted,
+  2008, 9, "M09", 6, 3, 24, 30, 0, 0, 0,
+  "calendar is changed if receiver has ISO calendar (1)",
+  "the era",
+  1909
+);
+
+assert.sameValue(
+  shifted.calendar,
+  cal,
+  "calendar is changed if receiver has ISO calendar (2)"
+);
diff --git a/test/intl402/Temporal/PlainDateTime/prototype/withPlainDate/argument-plaindate-calendar-same-id.js b/test/intl402/Temporal/PlainDateTime/prototype/withPlainDate/argument-plaindate-calendar-same-id.js
new file mode 100644
index 0000000000..2849905981
--- /dev/null
+++ b/test/intl402/Temporal/PlainDateTime/prototype/withPlainDate/argument-plaindate-calendar-same-id.js
@@ -0,0 +1,40 @@
+// Copyright (C) 2022 Igalia, S.L. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-temporal.plaindatetime.prototype.withplaindate
+description: PlainDate calendar is preserved when both calendars have the same id
+features: [Temporal]
+includes: [temporalHelpers.js]
+---*/
+
+const cal1 = {
+  toString() { return "this is a string"; },
+};
+const cal2 = {
+  id: 'thisisnotiso',
+  era() { return "the era"; },
+  eraYear() { return 1909; },
+  toString() { return "this is a string"; },
+  year() { return 2008; },
+  month() { return 9; },
+  monthCode() { return "M09"; },
+  day() { return 6; }
+};
+const pdt = new Temporal.PlainDateTime(1995, 12, 7, 3, 24, 30, 0, 0, 0, cal1);
+const pd = new Temporal.PlainDate(2010, 11, 12, cal2);
+const shifted = pdt.withPlainDate(pd);
+
+TemporalHelpers.assertPlainDateTime(
+  shifted,
+  2008, 9, "M09", 6, 3, 24, 30, 0, 0, 0,
+  "calendar is changed with same id (1)",
+  "the era",
+  1909
+);
+
+assert.sameValue(
+  shifted.calendar,
+  cal2,
+  "calendar is changed with same id (2)"
+);
diff --git a/test/intl402/Temporal/PlainDateTime/prototype/withPlainDate/argument-plaindate-calendar-same-object.js b/test/intl402/Temporal/PlainDateTime/prototype/withPlainDate/argument-plaindate-calendar-same-object.js
new file mode 100644
index 0000000000..f963a3b61d
--- /dev/null
+++ b/test/intl402/Temporal/PlainDateTime/prototype/withPlainDate/argument-plaindate-calendar-same-object.js
@@ -0,0 +1,42 @@
+// Copyright (C) 2022 Igalia, S.L. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-temporal.plaindatetime.prototype.withplaindate
+description: PlainDate calendar is preserved when both calendars are the same object
+features: [Temporal]
+includes: [temporalHelpers.js]
+---*/
+
+let calls = 0;
+const cal = {
+  id: 'thisisnotiso',
+  era() { return "the era"; },
+  eraYear() { return 1909; },
+  toString() {
+    ++calls;
+    return "this is a string";
+  },
+  year() { return 2008; },
+  month() { return 9; },
+  monthCode() { return "M09"; },
+  day() { return 6; }
+};
+const pdt = new Temporal.PlainDateTime(1995, 12, 7, 3, 24, 30, 0, 0, 0, cal);
+const pd = new Temporal.PlainDate(2010, 11, 12, cal);
+const shifted = pdt.withPlainDate(pd);
+
+TemporalHelpers.assertPlainDateTime(
+  shifted,
+  2008, 9, "M09", 6, 3, 24, 30, 0, 0, 0,
+  "calendar is unchanged with same calendars (1)",
+  "the era",
+  1909
+);
+
+assert.sameValue(
+  shifted.calendar,
+  cal,
+  "calendar is unchanged with same calendars (2)"
+);
+assert.sameValue(calls, 0, "should not have called cal.toString()");
diff --git a/test/intl402/Temporal/PlainDateTime/prototype/withPlainDate/argument-plaindate-calendar.js b/test/intl402/Temporal/PlainDateTime/prototype/withPlainDate/argument-plaindate-calendar.js
new file mode 100644
index 0000000000..ad9f56f7bb
--- /dev/null
+++ b/test/intl402/Temporal/PlainDateTime/prototype/withPlainDate/argument-plaindate-calendar.js
@@ -0,0 +1,38 @@
+// Copyright (C) 2022 Igalia, S.L. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-temporal.plaindatetime.prototype.withplaindate
+description: Original PDT calendar is preserved with ISO PlainDate
+features: [Temporal]
+includes: [temporalHelpers.js]
+---*/
+
+const cal = {
+  id: 'thisisnotiso',
+  era() { return "the era"; },
+  eraYear() { return 1909; },
+  toString() { return "this is a string"; },
+  year() { return 2008; },
+  month() { return 9; },
+  monthCode() { return "M09"; },
+  day() { return 6; }
+};
+const pdt = new Temporal.PlainDateTime(1995, 12, 7, 3, 24, 30, 0, 0, 0, cal);
+const pd = new Temporal.PlainDate(2010, 11, 12);
+assert.sameValue(pd.calendar.toString(), "iso8601", "PlainDate with ISO calendar");
+const shifted = pdt.withPlainDate(pd);
+
+TemporalHelpers.assertPlainDateTime(
+  shifted,
+  2008, 9, "M09", 6, 3, 24, 30, 0, 0, 0,
+  "calendar is unchanged if input has ISO calendar (1)",
+  "the era",
+  1909
+);
+
+assert.sameValue(
+  shifted.calendar,
+  cal,
+  "calendar is unchanged if input has ISO calendar (2)"
+);
diff --git a/test/intl402/Temporal/PlainDateTime/prototype/withPlainDate/argument-string-iso-calendar.js b/test/intl402/Temporal/PlainDateTime/prototype/withPlainDate/argument-string-iso-calendar.js
new file mode 100644
index 0000000000..d86925d1b8
--- /dev/null
+++ b/test/intl402/Temporal/PlainDateTime/prototype/withPlainDate/argument-string-iso-calendar.js
@@ -0,0 +1,36 @@
+// Copyright (C) 2022 Igalia, S.L. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-temporal.plaindatetime.prototype.withplaindate
+description: Original PDT calendar is preserved with ISO string
+features: [Temporal]
+includes: [temporalHelpers.js]
+---*/
+
+const cal = {
+  id: "thisisnotiso",
+  era() { return "the era"; },
+  eraYear() { return 1909; },
+  toString() { return "this is a string"; },
+  year() { return 2008; },
+  month() { return 9; },
+  monthCode() { return "M09"; },
+  day() { return 6; }
+};
+const dt = new Temporal.PlainDateTime(1995, 12, 7, 3, 24, 30, 0, 0, 0, cal);
+const shifted = dt.withPlainDate("2010-11-12");
+
+TemporalHelpers.assertPlainDateTime(
+  shifted,
+  2008, 9, "M09", 6, 3, 24, 30, 0, 0, 0,
+  "calendar is unchanged if input has ISO calendar (1)",
+  "the era",
+  1909
+);
+
+assert.sameValue(
+  shifted.calendar,
+  cal,
+  "calendar is unchanged if input has ISO calendar (2)"
+);