Hi, I'm a prospective student too. I'm pretty sure they put you on a waitlist if you missed the deadline. The way it works I think, is that the people who submitted the form before you get placed in rez first and only if there are any extra places left will you get a room. So if you were the first person to submit your application after the deadline, you'd be put first on the waitlist, and if you were the 50th person, you'd be placed 50th on the waitlist. The further back you are on the waitlist, the lower the chances that you'll be getting into rez but only McMaster Housing could tell you for sure. Your best bet would be to email
[email protected] r.ca and ask them. They're really helpful and respond very quickly.
Good Luck!!