Summaries for 3 upcoming episodes are up there. Nothing concerning 19 is really new, but 20 has that "something" that's going to happen during her performance. My guess is that Braixen evolves, but it can also be a bad thing (because I think she will lose).

Lastly, Dawn is not returning, and that episode sounds like a hilarious episode.

-:EDIT:-

Ok, no. Episode 20 is definitely a bad thing.