Barely a day after learning that director Bryan Singer will step behind the camera for 2016's X-Men: Apocalypse, a new interview with X-Men: Days of Future Past screenwriter Simon Kinberg clarifies who might be in front of the camera for the sequel.

"In Apocalypse, it will really to be the continuation of the 'past' of Days of Future Past," he told Yahoo Movies. That means the film seems poised to continue the Magneto/Xavier/Mystique through-line that began in 2011's X-Men: First Class.

Working in familiar faces from the future portions of Days of Future Past could prove difficult due to Apocalypse's setting. The film has been confirmed to take place in the 1980s, more than a decade after the 1970s portions of Days of Future Past, yet still two decades before the setting of 2000's X-Men. If Singer wants to make use of old favorites like Cyclops, Storm and Jean Grey, they'll have to recast the roles -- a idea that Kinberg addresses.

"It'd be very hard to do, because Halle, Famke, and Jimmy and others have done such wonderful jobs of bringing those characters to life," he said. "But I also would have said before First Class that there would be no actors who can stand alongside Ian McKellen and Patrick Stewart."

Considering how successful Michael Fassbender and James McAvoy have been in the roles originated by McKellen and Stewart, Kinberg's comment about the difficulties of recasting should not necessarily dash dreams of seeing a young Storm or Jean Grey in the film.

X-Men: Apocalypse opens in May 2016.