Duke
Louisville
Wake Forest
Georgia Tech
Miami FL
Syracuse
Pittsburgh
Boston College
Stanford
Cal
3 of those teams would need to be taken by either Big Ten or SEC of they both went to 24 schools. Teams in contention for B1G would be Notre Dame, North Carolina, Virginia, Duke, Clemson, Florida St, Stanford, and Cal. My gut says they'd add those first 3 on the list along with 1 of the other 5. I don't think Stanford or Cal are in play for the SEC so if they don't get the B1G then it's either Big 12 or bust for them. I'm going to say Notre Dame, UNC, Virginia, and Stanford in the Big Ten.
It will the be interesting to see what the SEC would do. I would assume Florida St and Clemson to the SEC in this scenario which brings them to 18. I also think they'd grab NC State and Virginia Tech to bring it to 20. If they were to go to 24, then the question would then be how much they prioritize overall athletic program quality vs strictly football quality vs access to a new market. I could see arguments for any for of the top 7 on the list above. They could also decide not to go to 24 teams.