The ACC is scheduled to have two exploratory calls in the next 24 hours to discuss Cal and Stanford potentially joining the conference, sources told Pete Thamel of ESPN.One of the calls is with ACC athletic directors, while the other will be with the league's presidents and chancellors, Thamel adds.Cal, Stanford, Oregon State, and Washington State are the only programs that remain in the Pac-12. There are "myriad options" being discussed among the schools on their next move, including a departure to the ACC, per Thamel.The ACC conference currently has 15 member schools across 10 states, including Duke, Miami, and Florida State, among others.Stanford has been in the Pac-12 since 1918, while Cal has been a member since 1915. Colorado, USC, UCLA, Washington, Oregon, Arizona, Arizona State, and Utah have already exited the Pac-12. The conference was founded in 1915.