How likely is it to be pulled off the waitlist for your IS? I don't understand how it works to be pulled off up until school starts. Is there a deadline for people to get back to the school if they are offered a spot off the waitlist? How do they move to the next candidate?
Each school will be a little different, so it’s always best to check with your school! They will tell you how long you have to make a choice when they make the waitlist offer, of course.
Following the 17 April deadline, most students will have made a choice, but there are often ripple effects. A seat opens at school A, and student 1 is called off the waitlist. Student 1 decides to take the seat at school A and gives up their seat at school B, where they had accepted before the deadline.
Now school B has to call someone off the waitlist, and so on, until the classes are once again filled.
Things happen, illness, accidents, etc that might cause someone to give up a seat or defer to the following year, which accounts for why seats may become available through the summer.
Most seats will be filled by the end of April, however. People may be called off the waitlist before the deadline if enough candidates decline their offers in advance. For example, Student X is accepted to 4 OOS schools and their IS. They know they’re going to attend their in state, so they can formally decline all of the OOS offers well in advance of the mid-April deadline, which can in turn cause movement on the OOS waitlists for those schools.