diff --git a/mod/assign/lib.php b/mod/assign/lib.php
index 2c2413416a6..8db3cbba94a 100644
--- a/mod/assign/lib.php
+++ b/mod/assign/lib.php
@@ -1613,6 +1613,14 @@ function mod_assign_core_calendar_provide_event_action(calendar_event $event,
             return null;
         }
 
+        $instance = $assign->get_instance();
+        if ($instance->teamsubmission && !$instance->requireallteammemberssubmit) {
+            $groupsubmission = $assign->get_group_submission($userid, 0, false);
+            if ($groupsubmission && $groupsubmission->status === ASSIGN_SUBMISSION_STATUS_SUBMITTED) {
+                return null;
+            }
+        }
+
         $participant = $assign->get_participant($userid);
 
         if (!$participant) {
diff --git a/mod/assign/tests/behat/group_submission.feature b/mod/assign/tests/behat/group_submission.feature
index 40e42beabb0..a82fb507780 100644
--- a/mod/assign/tests/behat/group_submission.feature
+++ b/mod/assign/tests/behat/group_submission.feature
@@ -28,6 +28,47 @@ Feature: Group assignment submissions
       | name    | course | idnumber |
       | Group 1 | C1     | G1       |
 
+  @javascript
+  Scenario: Confirm that group submissions are removed from the timeline
+    Given the following "activity" exists:
+      | activity                            | assign               |
+      | course                              | C1                   |
+      | name                                | Test assignment name |
+      | assignsubmission_onlinetext_enabled | 1                    |
+      | teamsubmission                      | 1                    |
+      | duedate                             | ##tomorrow##         |
+      | requiresubmissionstatement          | 1                    |
+    And the following "group members" exist:
+      | user     | group |
+      | student1 | G1    |
+      | student2 | G1    |
+    # Student1 checks the assignment is visible in the timeline
+    When I am on the "Homepage" page logged in as student1
+    Then I should see "Test assignment name" in the "Timeline" "block"
+    # Student2 checks the assignment is visible in the timeline
+    And I am on the "Homepage" page logged in as student2
+    And I should see "Test assignment name" in the "Timeline" "block"
+    # Student2 submits the assignment
+    And I am on the "Test assignment name" Activity page
+    And I press "Add submission"
+    And I set the field "Online text" to "Assignment submission text"
+    And I press "Save changes"
+    And I should see "Draft (not submitted)" in the "Submission status" "table_row"
+    And I press "Submit assignment"
+    And I should see "This submission is the work of my group, except where we have acknowledged the use of the works of other people."
+    And I press "Continue"
+    And I should see "Confirm submission"
+    And I should see "- Required"
+    And I set the field "submissionstatement" to "1"
+    And I press "Continue"
+    And I should see "Submitted for grading" in the "Submission status" "table_row"
+    # Student2 checks the timeline again
+    And I am on the "Homepage" page
+    And I should not see "Test assignment name" in the "Timeline" "block"
+    # Student1 checks the timeline again
+    And I am on the "Homepage" page logged in as student1
+    And I should not see "Test assignment name" in the "Timeline" "block"
+
   @javascript
   Scenario: Switch between group modes
     Given the following "activity" exists:
diff --git a/mod/assign/tests/lib_test.php b/mod/assign/tests/lib_test.php
index 5fad64323d4..0b97b37df0e 100644
--- a/mod/assign/tests/lib_test.php
+++ b/mod/assign/tests/lib_test.php
@@ -520,6 +520,69 @@ class lib_test extends \advanced_testcase {
         $this->assertTrue($actionevent->is_actionable());
     }
 
+    /**
+     * Test group submissions.
+     * @covers \assign::mod_assign_core_calendar_provide_event_action
+     */
+    public function test_assign_core_calendar_provide_event_action_duedate_for_group_assignment(): void {
+        $this->resetAfterTest();
+        $course = $this->getDataGenerator()->create_course();
+        $teacher = $this->getDataGenerator()->create_and_enrol($course, 'teacher');
+        $student1 = $this->getDataGenerator()->create_and_enrol($course, 'student');
+        $student2 = $this->getDataGenerator()->create_and_enrol($course, 'student');
+        $group = $this->getDataGenerator()->create_group([
+            'courseid' => $course->id,
+        ]);
+        groups_add_member($group->id, $student1->id);
+        groups_add_member($group->id, $student2->id);
+
+        $assign = $this->create_instance($course, [
+            'assignsubmission_onlinetext_enabled' => 1,
+            'requiresubmissionstatement' => 1,
+            'teamsubmission' => 1,
+            'completion' => 0,
+            'completionsubmit' => 1,
+        ]);
+
+        // Create a calendar event.
+        $this->setAdminUser();
+        $event = $this->create_action_event($course, $assign, ASSIGN_EVENT_TYPE_DUE);
+        $this->setUser();
+
+        $factory = new \core_calendar\action_factory();
+        $actionevent1 = mod_assign_core_calendar_provide_event_action($event, $factory, $student1->id);
+        $actionevent2 = mod_assign_core_calendar_provide_event_action($event, $factory, $student2->id);
+
+        // Confirm the events were decorated.
+        $this->assertInstanceOf('\core_calendar\local\event\value_objects\action', $actionevent1);
+        $this->assertEquals(get_string('addsubmission', 'assign'), $actionevent1->get_name());
+        $this->assertInstanceOf('moodle_url', $actionevent1->get_url());
+        $this->assertEquals(1, $actionevent1->get_item_count());
+        $this->assertTrue($actionevent1->is_actionable());
+
+        $this->assertInstanceOf('\core_calendar\local\event\value_objects\action', $actionevent2);
+        $this->assertEquals(get_string('addsubmission', 'assign'), $actionevent2->get_name());
+        $this->assertInstanceOf('moodle_url', $actionevent2->get_url());
+        $this->assertEquals(1, $actionevent2->get_item_count());
+        $this->assertTrue($actionevent2->is_actionable());
+
+        // Submit as the student.
+        $this->add_submission($student1, $assign);
+        $this->submit_for_grading($student1, $assign, ['submissionstatement' => 'Hello, world!']);
+
+        // Create a new calendar event.
+        $this->setAdminUser();
+        $event = $this->create_action_event($course, $assign, ASSIGN_EVENT_TYPE_DUE);
+        $this->setUser();
+
+        // Confirm there were no events to action.
+        $actionevent1 = mod_assign_core_calendar_provide_event_action($event, $factory, $student1->id);
+        $this->assertNull($actionevent1);
+
+        $actionevent2 = mod_assign_core_calendar_provide_event_action($event, $factory, $student2->id);
+        $this->assertNull($actionevent2);
+    }
+
     public function test_assign_core_calendar_provide_event_action_gradingduedate_as_teacher() {
         $this->resetAfterTest();
         $course = $this->getDataGenerator()->create_course();