Bring in the schools early so that they can build their brand in a true P5. Once Oklahoma and Texas leave, you are no longer P5, and they no longer get potential home games.
If you wait until Texas and Oklahoma leave, you are bringing in "non-P5 teams" which will not have as positive a perception.
To summarize: if you care about the conference, bring in teams early. If you care about the money, hold off on new teams until Texas and Oklahoma leave. I am guessing the Little 8 will cheap, and repeat the error they made on not inviting teams years ago.
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