I think it'd have to have to be put into motion pretty soon here though. With the huge timeline-altering effects of DOFP, the new Alternate Dimension power origin of the FF, new major characters that are being introduced such as Deadpool and Gambit (ok well they both had minor way-worse versions in now retconned films) who - absent a big change in the universe/timeline it doesn't make sense how we wouldn't have seen or heard of them somewhere along the way - and the seemingly likely major changes that will be coming with Apocalypse -- Now is the time to start implementing it if they ever are going to. The concepts of alternate universes and alternate timelines are not only central plot points to these recent movies, but they are finally and interestingly coming about in a relatively short period of time (considering how long the Xmen Franchise has been going for Fox). Additionally, this could be a great (and perhaps only remaining) way to reboot/recast Wolverine now that Jackman will be done after his next solo. If you can, in one giant move, make a decently plausible story for your best character to be recast, connect these new/new versions of characters that are giong to be getting solo movies (Deadpool, etc) which could tie in with the future X-Force movie, AND connect in your other big Franchise... how do you not do it at a time when Time travel/alternate timelines and alternate universes are at a forefront of your studios' storytelling? Alternatively, I think this would be the best way to also tie in any of Fox owned properties to the MCU down the road if - like Sony - they eventually quit being so financially successful and give Fox incentive to make a deal. Combining elements of Xmens Time stuff and FF alternate dimensions, with the MCU's (albeit very brief thus far) introudction to different realities and the upcoming Infinity War story that will reveal way more about all of this, would make it plausible for these characters to be brought into the MCU and not be like "huh? where were all these guys when Loki was attacking NY or Ultron tried to destroy the world?"