From another article:

"Allen said they're still trying to figure out what to call the University of Chicago, since it is not a member of the athletic conference, but the change won't impact their role in the alliance.

"They'll continue to be a partner institution, and we're working on what we'll call that," Allen said. "The relationship will continue to be very strong, they'll just have a different name."

From the one you linked:

"A spokesman for Chicago said via email that while the university "will not be a formal member going forward, we plan to continue our academic collaborations with the organization and its member institutions. We are currently working with the consortium to continue our participation in the programs related to library services, IT, language instruction and other areas that benefit our campus as well as the broader academic community."