“You may think that’s a hell of a long time. Personally, I think that’s a hell of a bird.”

STOP

If Steven Moffat had written Cause and Effect, it would have skipped to the crew escaping the time loop with no explanation; and if you asked him how they got out of it, he’d just laugh at you for caring.

(ETA: I feel like I should be clear that I’m not a fan of Moffat.)