At the conclusion of UFC 226, Brock Lesnar entered the cage to set up a future fight against new two-division champ, Daniel Cormier. The only issue is, Lesnar can’t actually fight yet. He still has time left on his suspension from his UFC 200 bout against Mark Hunt.
Lesnar left the registered testing pool midway through his suspension, and per the UFC’s anti-doping policy, he still has to serve the remainder of his suspension, and/or six months in the pool due to his retirement while suspended. He only has to serve whichever of those two periods of time is longer.