User blog comment:Gundam Legilis/Fall In Depth/@comment-11188061-20151217045417/@comment-26397825-20151217045726

Because the next episode starts with her coming out of the elevator and asking why Ozpin called her up there. Then have have the big reveal, and Pyrrha is later seen standing at the finals in the tournament looking very conflicted, which suggests that it really was her. I doubt Neo is going to be able to pretend to be Pyrrha in a fight after all, considering a lot of Pyrrha's fighting style revolves around her semblance.