WWE issued an official statement saying
Brock Lesnar remains under contract to WWE, however, he has been granted a one-off opportunity to compete at UFC 200. Following this milestone event on July 9, Brock will return to WWE for SummerSlam on Sunday, August 21, live on WWE Network.
The event will be headlined by Daniel Cormier vs John Jones for the light heavyweight title and the co main event will pit Lesnar against a TBA opponent. Also at the event will have Miesha Tate defending her battemweight title against Amanda Nunes, and the interim featherweight title will be up for grabs as Jose Aldo takes on Frankie Edgar. It all goes down Saturday July 9th live on PPV