As it stands right now, BYU will not be invited to any P5 conference. There would have to be some huge shake-ups in the conferences for a slot to open for BYU into the P12 or B12. I don't see that happening right now.
The AAC doesn't need BYU. They are in the driver's seat for the 6th playoff spot. Another team could sneak in from the MWC/C-USA/MAAC on occasion, but the AAC will be the heavy favorite to produce a team each year. Adding BYU doesn't help their odds in any way whatsoever. In fact, it decreases it. They don't need more parity. They want a spotless or 1 loss champ now.