For those of you wondering, yes, Ash is going to defeat Alain and win the League. The Team Flare arc soon after will then last about four-five episodes, concluding in the one-hour storyline. Post Team Flare, Ash will learn more about Greninja's Hero form and will then be directed to Alola, where the Champions League will happen to be. But before he can go there, he will still need to defeat Champion Diantha in order to accept such an esteemed honor.

While the Sun and Moon anime will ultimately be about Ash's preparation for the Champions League, he will use the time he has to partake the Alolan trials in order to further strengthen his new team. He will be bringing Pikachu and Greninja along with him at first, but he will ultimately be building up an entirely new team. Serena will eventually join Ash to Alola.

Ash's third traveling will be the male protagonist of Sun and Moon, who will also be taking part in the island trials. And outside of that, there will be a fourth travelling companion who will be rotating frequently all throughout the series.

The Sun and Moon anime is designed specifically to serve as a passing-of-the-torch of sorts, as Ash's journey to become Pokémon Master is nearing an end, so the male protagonist is being groomed to succeed Ash.