Most schools follow AACMAS suggestions, so after February most schools give you only two weeks. If you are taken off the waitlist in the summer, they may require it "immediately". You'll have to ask the school how soon that is in their estimate.
eh, i'm the point where i'm already accepted to the school i want so i'm already withdrawing the late interviews and waitlists so that other people can have a better chance. so hopefully that will help you out but i can't guarentee anything 😉. besides, we're already attending a kick *** school 😀