Timing of the invitation message	Date
Time 1: Five weeks before the test	March 5, 2016
Time 2: Four weeks before the test	March 12, 2016
Time 3: Three weeks before the test	March 19, 2016
Time 4: Test day	April 9, 2016
Time 5: One week after the test	April 16, 2016
Time 6: Three weeks after the test	April 30, 2016