Originally, Rogue was supposed to be in the film but then it was reported that her scenes would be cut out. Now, it has been confirmed by 20th Century Fox that Rogue will be in the movie albeit in a cameo role only.
Getting to the point, over on the website Vulture, they have allegedly revealed Rogue's role in the film in detail. So here's your potential SPOILER ALERT and read on at your own risk after the image below.
"Days of Future Past begins in a dystopian future where the few remaining mutants are being hunted by fearsome robotic Sentinels, and both Professor X (Patrick Stewart) and Magneto (Ian McKellen) decide they can change their present by sending Wolverine (Hugh Jackman) into the past, where he can alter the course of history that will eventually lead to those Sentinels being created. To do this, they employ mutant Kitty Pryde (Ellen Page), who is able to project Wolverine's consciousness back in time and into his younger body.
"While Wolverine is gallivanting around in the past with the X-Men: First Class cast, though, Kitty Pryde is injured, and her future hold on Wolverine becomes tenuous. In order to preserve the time travel bond, then, the X-Men must find Rogue, who has the ability to absorb any mutant power.
"Unfortunately, Rogue is being held prisoner at Xavier Mansion, which has been transformed into a Sentinel-guarded military base, and the mission to find and rescue her — an expensive, lengthy sequence that involves Professor X, Magneto, and Iceman (Shawn Ashmore) — was sliced from the film in postproduction after Fox executives worried it would pad the running time to over two and a half hours. Rogue is still brought in briefly to absorb Kitty's power and tend to Wolverine, but the machinations to get her there will now happen offscreen."
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