Covered by newly created PHPUnit Manual testing as below Initial setup Navigate to Site Administration> Users > Define roles. Edit the Teacher role. Filter the moodle/site:accessallgroups Uncheck the Allow checkbox. Save changes. Create 4 accounts called: s1 , s2 , t1 , and t2 . Create 2 courses called C1 and C2 with Group mode: Separate groups Force group mode: Yes Enrol s1 as a student to C1 . Enrol t1 as a teacher to C1 . Create a group called G1 in C1 . Add s1 and t1 to G1 group C1 course. Enrol s1 and s2 as students to C2 . Enrol t1 and t2 as teachers to C2 . Create a group called G1 in C2 . Create a group called G2 in C2 . Add s1 and t1 to G1 group in C2 course. Add s2 and t2 to G2 group in C2 course. Create a Quiz activity called C1-Q1 in a C1 course: Open: Today , Close: 5 days later . Create a Quiz activity called C2-Q1 in a C2 course: Open: Today , Close: 5 days later . Testing Login as t1 . Navigate to C1. Navigate to C1-Q1 Quiz. Click More > Overrides. Change the tertiary navigation to Group overrides. Click the Add group override button. Group: G1. Open the Quiz: +1 day. Close the Quiz: +1 day Save. Navigate to C2. Navigate to C2-Q1 Quiz. Click More > Overrides. Change the tertiary navigation to Group overrides. Click the Add group override button. Group: G1. Open the Quiz: +1 day. Close the Quiz: +1 day Navigate to Dashboard. Verify in the Calendar block: Verify that you will see C1-Q1 - G1 opens event. Verify that you will see C2-Q1 - G1 opens event. Verify that you will see C1-Q1 - G1 closes event. Verify that you will see C2-Q1 - G1 closes event. Log in as t2 . Navigate to Dashboard Verify in the Calendar block: Verify that you will not see C1-Q1 - G1 opens event. Verify that you will not see C2-Q1 - G1 opens event. Verify that you will not see C1-Q1 - G1 closes event. Verify that you will not see C2-Q1 - G1 closes event. Verify that you will see C2-Q1 opens event ( The original date ) Verify that you will see C2-Q1 closes event ( The original date )