[@Burning Kitty][@Silver Carrot]Carrot has a point, though I'm not sure if they're asking "why did she change" or "why would we need to react".

As for the second question, we don't really need to react that much. The school probably has a shapeshifter or two, aside from mystique herself. Not to mention in a place where people can shoot lasers out of their eyes and control the weather, people looking like other people isn't [i]that[/i] big of a deal, especially on their own side.