Probably several more
IMO the mechanics of how the media generates revenues suggest 24+ in each P2 possible
Realignment is about consolidation of viewers to the P2 game in the three prime windows during the week (noon, 3:30, primetime). At some level, they’re willing to add to prevent a 3rd conference from being able to cannibalize their matchups.
Before streaming, they were a bit capped at how many they could take at a premium rate due to the lack of premium windows. But with streaming they can hide more of their weekly excess inventory from casual viewers, but still getting paid well due to subscriptions. And bundling a lot of schools drives more subscribers.
So expansion guts 3rd conference from taking casual viewers, concentrating even more fans to their featured games. It mitigates any threat a new media entrant can gain footing, and helps drive subscribers. It means sharing even less of postseason revenues/berths, including the coming new CBB postseason deal. It lowers political risk due to achieving a big tent.
And if the market for rights increases regardless, they’ll be able to hide that some new additions are below current average