The in-game info shows that the next tournament will be Marble, a week from now. Makes it seem like we're skipping the Gems tournament.
Possibly related to that: As was already reported elsewhere, currently the in-game info about last turnament shows the results of the ELIXIR tournament even though the last one was Magic Dust.
@Dizzy Lizzie Could you check this, please? I hope this isn't just because they are going to use the EN server as a second test of the Challenges. Especially since Marindor (on Beta) already assured us that the Challenges are not meant as a replacement for the tournaments, that we will be able to have both active at the same time, and that canceling the Magic Dust tournament on Beta was a one-time thing. There should be no need to cancel the Gems tournament just to introduce the Challenges.