Only P2 conferences from that point. They won’t leave any schools that’ll add weight against them.
But, if the ACC stays intact, with the Pac adding the Big12 Texas schools, and having a loose partnership with the ACC, then that would create a P3.
In this scenario (a loose partnership/alliance), I personally think the Pac adding Big12 teams makes more sense than the Big12 adding Pac teams. And so bringing in the Texas schools will bridge the two coast, although it’ll be part of a west division.
Again speculation. Makes more sense on paper without running real numbers.