There are four contests during the regular season. The window during which each contest can be accessed on HackerRank is as follows.
Contest #1: available Nov. 1, 2021; closes Sunday January 16, 2022 @ 11:59pm EST
Based on the scores during the regular season, top students in all divisions will be invited to participate in an online Finals competition:
Invitations E-mailed: May 1, 2022 through May 16, 2022
Invitational Finals: Saturday, May 28, 2022 (Memorial Day weekend in the United States)
There is a $25 per-student registration fee to participate in the Finals.
More details are available in the Finals page.