>>32952389They've already distributed all of the Event Fodder, and will have all of the Cap Pikachu out of the way by the end of the year.
USUM won't be able to hold down the fort for long.
The anime's already about halfway through Alola, and with 20-25 Episodes between each Grand Trial, we'll be reaching the last Grand Trial right about the time Gen 8 is properly revealed and on the horizon, wherein Ash graduates and finds out about the next region, no tournament or anything because the League hasn't been created.
It's all aligning for Gen 8 to be released Holiday Season '18.