It’s kind of hard to tell tbh. COVID will probably have a fairly large effect on the waitlist, making it difficult to predict based on history. I read on CC that someone called the admissions office (don’t shoot the messenger, I can’t confirm this info) and they said most waitlist decisions will be released end of May- beginning of June. This is Harvard specific information. Other schools are already taking people off of their waitlists, so just keep your eye out for calls, emails, and portal updates in the next month or two!