X-Men: First Class Sequel To Begin Shooting January 2013
Initially Fox wanted to start this Fall, but ran into a conflict with Lionsgate over Jennifer Lawrence and the filming for the sequel to The Hunger Games, Catching Fire.
Apparently there was a bit of tension among the two studios as Fox wanted Lawrence for the Fall shoot, reprising her role as the shape-shifting mutant Mystique, while Lionsgate planned on a Summer shoot for The Hunger Games sequel with a November 2013 release.
As Lawrence signed on to X-Men: First Class before The Hunger Games, Fox actually has first dibs.
However, Fox has now gone for the later January date, leaving the schedule open for Lionsgate to begin filming.
"X-Men: First Class 2" currently has no release date.