Actually, I'm beginning to wonder, could Sun and Moon be the last anime series? I mean, although Ash has participated in leagues before, this is the first time he's participated in one that's literally starting up the time he's in the region. Plus, he made Misty and Brock promise that they return for Alola, rather than him doing the promising, which is definitely unprecedented in many ways. And we also know that we're about midway through the saga and are coming very close to the climax due to Lillie's mom appearing and Cosmog playing a more prominent role in later episodes. Ash may actually become champion of the Alola league very soon, especially considering that, technically, it will be the very first league for Alola, so there's little competition there.