I read for someone that Bishop will come back as villain. It's ok. I believe that Bishop is more hero than any x-man because he had the balls to protect humanity by himself because he want to prevent that any human and heroes suffer what he had suffer in a timeline where everything was destroy, enslaved, and ruled by the sentinels. If he return as villains, then is a great ideal for him to form his own villain team that can take revenge of anyone who treated him as a traitor and make the X-Men suffer in all sense of the word.
Omega Weapon: Their terminator