A new rumor started by El Mayimbe suggests that X-Men: Apocalypse may get its name from more than it's villain, but because it's one of two films that will end the X-Men Cinematic Universe as we know it. According to Mayimbe, X-Men: Apocalypse and the third Wolverine solo movie will be final installments in the X-Men film universe begun in Bryan Singer's 2000 X-Men movie.
On one hand, with stars like Hugh Jackman, Jennifer Lawrence, and Nicholas Hoult all ending their tenure with the franchise following Apocalypse and the next Wolverine, now seems like a pretty good time to reboot if they're going that route, and may tie into rumors of an X-Men crossover with the newly rebooted Fantastic Four franchise.
On the other hand, X-Men: First Class was probably a much better opportunity to reboot the franchise, one that Fox passed up, and to reboot now would render all of the continuity clearing that was accomplished with X-Men: Days of Future Past a moot point.
The rumor also doesn't address the status of other currently in development films like, like Deadpool and Gambit, which were at least conceived as being tied to the current X-Men movie universe.
World ending or otherwise, X-Men: Apocalypse is currently filming and will hit theaters May 27, 2016.