What does someone do if they have an A but are waitlisted to their dream school that takes people off the waitlist all the way into July?

What does someone do if they have an A but are waitlisted to their dream school that takes people off the waitlist all the way into July? Is it possible to say that one would matriculate to the A school, hold onto the waitlist spot, be accepted last week of July, drop the initial A, and matriculate at the dream school, or does AAMC not allow that with the April 30th deadline? Thank you.
Source: Student Doctor Network - Category: Universities & Medical Training Authors: Tags: Pre-Medical (MD) Source Type: forums