Is Days of Future Present the next X-men film?

The Internet is a buzz with Bryan Singer mentioning the possibility of an X-Men Fantastic Four cross over. Since Fox has the cinematic rights to both the mighty mutants and Marvel's first family it is plausible they may be trying to create their own cinematic universe similar to Disney's MCU . I've heard numerous outlets postulating that the cross over X-Men vs The Fantastic Four as the obvious adaption. However my money is on Days of Future Present. The reason that's my guess is Bryan Singer the steward of cinematic mutant franchise has stated the ground work is already set for a F.F. X-Men crossover. What might that ground work be? 

1) Days of Future Present is a sequel to Days of Future Past and deals heavily with the future incarnation of Reed Richard's (Mr. Fantastic) and Sue Storm's (The Invisible Woman) son (Franklin Richards) and the potential future offspring(Rachel Summers) of Jean Grey (Marvel Girl/Phoenix) and Scott Summers (Cyclops).

2) X-Men Apocalypse (2016) is an 80's period film. The two previous X-films took place in the 70's and 60's respectively. If they are going in chronological order which decade is next? Yup, the 90's the decade Days of Future Present takes place in.

I hope you enjoyed going down this continuity rabbit hole as I did writing it.