If time exists inside our universe, and passes as it appears to pass, A-theory of time is true. If a reality exists outside of spacetime, time is only an illusion. From this perspective, our past, present, and future happen at the same time.
So if we call the extraverse, our universe plus any reality removed from spacetime, we have two different theories of time alive in the same system. Inside the universe we have A-theory of time, and outside the universe we have (looking at the universe) B-theory of time.
So this is what I call C-theory of Time: A-theory in our universe, and B-theory of time observing our universe from the exterior perspective. Time is real inside spacetime but illusory outside of it.