Apparently it was a recap from CinemaCon

http://www.blastr.com/2014-3-27/firs...spoilers-ahead

Sentinels are dispatched to find and kill mutants living underground. Their delivery system (and the world) is reminiscent of The Matrix, but once the Sentinels - who can adapt to any situation and change their form - drill into the secret base it gets real good. The mutants on hand: Sunspot, Iceman, Bishop, Kitty Pryde, Blink and Warpath. Kitty Pryde and Bishop immediately run off while the other X-Men keep the semi-liquid metal robots busy. There are good action beats using the characters’ powers, especially Blink, whose portals allow Warpath to do some really fun run and jumps onto the Sentinels. Iceman glides around on an ice slide, and Sunspot becomes a being of lava and fire as he blasts robots. Kitty and Bishop (who uses Sunspot’s fire to charge his big dumb gun) are running off to a closet someplace. Bishop lays down and Kitty starts massaging his temples, and it becomes clear that she’s sending his consciousness back in time. The others are buying them minutes… with their lives. A Sentinel snaps Sunspot’s neck. Iceman has his head popped off and is crushed underfoot. Blink gets skewered. Warpath gets blasted to smithereens. But it was worth it! As the Sentinel breaks into the closet, blasting fire, Kitty looks up and says, “Too late, asshole!” and everything disappears. The past has been changed.