I brought it up once and people thought I was kind of crazy.
But everyone talks about the P12, the B12, and the B10 adding teams. Some people think it is an inevitable eventuality. The only options for P5 conferences are to raid each other, or add non-P5.
Without beating the point to death, it seems like a true possibility (one of many) that BYU would be the best option for more than one conference. Indeed, absent the collapse of the B12, BYU seems like the best candidate, should any of those conferences decide to expand.