"70 Million Years BC… And Then Some!"
The Fantastic Four discover that the island is spread out in time zones and the earliest parts are reverting back into their correct era. So the FF head to the furthest point of the island and begin building a raft so they can get off the island and stay ahead of the time recall. But they run into a wall where the time bubble ends and it takes a few tires to penetrate the bubble before the entire island disappears. Now outside of the bubble, the FF regain their powers as they wait to be rescued.