>>24766136>>24766151>>24766319Remember that Mega Charizard Y was in the calendar leak, which predates the XYZ reveal, along with Noivern and Sylveon. Noivern and Sylveon have been teased a lot recently, so it's only a matter of time until they do the same for Charizard Y.
The biggest question is how soon will we see the second version of the current opening? How will Charizard, Mudkip, Sylveon, and Noivern fit into it? My guess is that the scene where Greninja walks away from Ash will be replace by an Ash/Alain scene that foreshadows the Charizard showdown. Reason why that scene will be replaced is because Ash and Greninja would be in perfect sync by then, so there wouldn't be any problems in their relationship. The Greninja vs Sceptile scene should be kept since the rivalry with Shota is just as important as the one with Alain. Also, Shota doesn't even have Mega Sceptile yet.