5 Ways To Improve The X-Men Timeline

Not knowing exactly where the show intends to go or how involved it will choose to be in the X-Men universe, there are possibilities available there and with David Haller a.k.a Legion's extensive abilities from the comics he has been able to effect time, much like in the Age of Apocalypse storyline. You also have the added bonus of him not having a great handle on what reality is and if he's crazy or not. His ability to effect time and his distorted perspective could account for the errors in continuity.

It may be a bit of a challenge to pop him into the cinematic universe but the only real connection needed to sell it is Xavier, whether that's an aged up McAvoy or Stewart coming back for a cameo. This could lead to many other story arcs, maybe even the Age of Apocalypse run itself, if the viewers could get behind seeing Apocalypse as a main villain once again and seeing yet another future timeline that would essentially be erased in the climax of that particular film. But putting that aside, the abilities he possesses could just as easily alter other aspects of time that don't have anything to do with Apocalypse making an encore.

This doesn't mean that the entire X-Men universe has to be from David's perspective either. It could really come down to a few simple hiccups in powers he has that he doesn't fully understand. Now, whether this is in a film or is part of a future episode of the series is really up to the creators, but the simple fact is that David's narrative is build off of a fractured reality and it seems to be one of the best places to suggest an answer to the X-Men timeline.