The Apocalypse “Twelve” event is over. UXM #379 basically begins with a lot of level-setting.
Cyclops is “dead.” Professor X is moping, and leaves on a spaceship to help the mutant skrulls from the prior story colonize a new planet. Kitty quits the team, along with Bishop, Jubilee, and a few others. Others play baseball, but Storm is daydreaming so Wolverine prevents her from getting a concussion.
Magneto, Quicksilver, Polaris and others are dealing with unrest in Genosha. The Legacy Virus is still a thing. Mystique is doing spy stuff. Blob is being a criminal.
After all that and more, this arc begins with High Evolutionary and Mister Sinister figuring out how to reverse the mutant gene and rendering everyone human.
So, everyone gets depowered amidst the drama above. They have their own little adventures and then the ending to this arc is rushed so that Chris Claremont can come back and write both X-books.