In addition, the AAC would probably want BYU to sign some contract penalizing them if they bolt to another league. BYU’s goal is a P5 league around 2024 when the rumors of the next wave of shuffling will happen. That’s why you don’t see BYU have more than like 3-4 games scheduled beyond 2024ish.
Since BYU puts in a clause to avoid penalties if they join a P5 conference, why would they not schedule games "beyond 2024ish"? No penalty for cancelling those games would be added incentive to schedule them.