Xmen Days of future past writer Simon Kinberg stated in a recent interview some new information regarding the next segment in the Xmen film universe.
Many fans are wondering if the next installment of the film will feature any of the original cast since lately the focus has been put a on the younger (first class) generation of mutants. Simon did confirm the original cast will be involved in telling the story. However they may not be the main focus of said story and will mainly involve the younger generation.
Fans are also wondering if Singer will return to direct this film. Singer was the first to announce this project via Twitter. So we can speculate he will be involved. This was before recent events involving lawsuits against the director surfaced.
When asked if Singer will be returning to direct [X-Men: Apocalypse](movie:1194267) Kinberg simply said "That's the plan"