The Big 12 Conference, soon to lose Oklahoma and Texas, apparently will soon add Brigham Young, Central Florida, Cincinnati and Houston, according to Sports Illustrated: https://www.si.com/college/2021/09/03/big-12-expansion-byu-houston-ucf-cincinnati?utm_medium=push_notifications&utm_source=pushly&utm_campaign=1343187
The SI article says it's even possible the four newcomers could join as early as 2023; the Sooners and Longhorns will depart for the Southeastern Conference no later than 2025. So the 10-team Big 12 could temporarily have 14 members.
BYU currently is a football independent whose other teams play in the West Coast Athletic Conference, whereas the other three have their entire programs in the American Athletic Conference.
BYU has a large, national fan base, Cincinnati gives West Virginia a nearby rival, UCF brings the Big 12 to recruiting-rich Florida and Houston adds a large metro area to the league. All four newcomers have been competitive in football, men's basketball and other sports and should help the Big 12 hold its own with the Big Ten, SEC, Pac-12 and Atlantic Coast Conference once OU and UT leave.