diff --git a/lib/behat/form_field/behat_form_date.php b/lib/behat/form_field/behat_form_date.php
index 030d8525992..903c15bdcda 100644
--- a/lib/behat/form_field/behat_form_date.php
+++ b/lib/behat/form_field/behat_form_date.php
@@ -56,17 +56,19 @@ class behat_form_date extends behat_form_group {
             // Disable the given date selector field.
             $this->set_child_field_value('enabled', false);
         } else if (is_numeric($value)) { // The value is numeric (unix timestamp).
-            // First, reset the day always to an existing one (1st). Without that
-            // undesired modifications (JS) happens when changing of month and day if
-            // the interim combination doesn't exists (for example, 31 March => 01 April).
-            // Note that instead of always setting the day to 1, this could be a little more
-            // clever, for example only changing when the day > 28, or only when the
-            // months (current or changed) have less days that the other. But that would
-            // require more complex calculations than the simpler line below.
-            $this->set_child_field_value('day', 1);
             // Assign the mapped values to each form element in the date selector field.
             foreach ($this->get_mapped_fields($value) as $childname => $childvalue) {
                 $this->set_child_field_value($childname, $childvalue);
+                if ($childname === 'enabled') {
+                    // As soon as the form is enabled, reset the day to an existing one (1st). Without that
+                    // undesired modifications (JS) happens when changing of month and day if
+                    // the interim combination doesn't exists (for example, 31 March => 01 April).
+                    // Note that instead of always setting the day to 1, this could be a little more
+                    // clever, for example only changing when the day > 28, or only when the
+                    // months (current or changed) have less days that the other. But that would
+                    // require more complex calculations than the simpler line below.
+                    $this->set_child_field_value('day', 1);
+                }
             }
         } else { // Invalid value.
             // Get the name of the field.
diff --git a/lib/tests/behat/datetime_any.feature b/lib/tests/behat/datetime_any.feature
index 5e8c236c4f6..8c78e02073e 100644
--- a/lib/tests/behat/datetime_any.feature
+++ b/lib/tests/behat/datetime_any.feature
@@ -5,7 +5,7 @@ Feature: Any day / month / year combination in date form elements works ok.
   Any day / month / year combination must work ok
 
   @javascript
-  Scenario Outline: Verify that setting any date / datetime is possible
+  Scenario Outline: Verify that setting any date / datetime is possible with enabled fields
     Given the following "courses" exist:
       | fullname | shortname | format |
       | Course 1 | C1        | topics |
@@ -30,3 +30,31 @@ Feature: Any day / month / year combination in date form elements works ok.
       | 1709186400   | 1740808800        | Saturday, 1 March 2025, 2:00           |                                            |
       | 1577858400   | 1577772000        | Tuesday, 31 December 2019, 2:00        | change of year, back and forth             |
       | 1577772000   | 1577858400        | Wednesday, 1 January 2020, 2:00        |                                            |
+
+  @javascript
+  Scenario Outline: Verify that setting any date / datetime is possible with disabled fields
+    Given the following "courses" exist:
+      | fullname | shortname | format |
+      | Course 1 | C1        | topics |
+    And the following "activity" exist:
+      | activity   | name          | intro                              | course | idnumber |
+      | assign     | Assignment 01 | Assign activity to test some dates | C1     | assign01 |
+    And I am on the "Assignment 01" "assign activity editing" page logged in as admin
+    And I expand all fieldsets
+    And I set the field "Due date" to "<initial_date>"
+    And I set the field "Due date" to "disabled"
+    And I set the field "Due date" to "<final_date>"
+    When I press "Save and display"
+    Then the activity date in "Assignment 01" should contain "Due:"
+    And the activity date in "Assignment 01" should contain "<date_result>"
+
+    Examples:
+      | initial_date | final_date        | date_result                            | case_explanation (times Australia/Perth)   |
+      | ##today##    | ##tomorrow noon## | ##tomorrow noon##%A, %d %B %Y, %I:%M## | change of day, any day, back and forth     |
+      | ##tomorrow## | ##today noon##    | ##today noon##%A, %d %B %Y, %I:%M##    |                                            |
+      | 1617256800   | 1617170400        | Wednesday, 31 March 2021, 2:00         | change of month, back and forth            |
+      | 1617170400   | 1617256800        | Thursday, 1 April 2021, 2:00           |                                            |
+      | 1740808800   | 1709186400        | Thursday, 29 February 2024, 2:00       | change of month, leap year, back and forth |
+      | 1709186400   | 1740808800        | Saturday, 1 March 2025, 2:00           |                                            |
+      | 1577858400   | 1577772000        | Tuesday, 31 December 2019, 2:00        | change of year, back and forth             |
+      | 1577772000   | 1577858400        | Wednesday, 1 January 2020, 2:00        |                                            |