I only know what’s in this spot from the Disney Channel website, but what it says there is the following.
This spring, the new home for Gravity Falls and Wander Over Yonder is Disney XD.
That does sound like new episodes will henceforth air on Disney XD. Maybe there’ll be a press release with more comprehensive information. There have already been promos and whole marathons of Wander Over Yonder reruns on Disney XD, which, in retrospect, could be seen as having foreshadowed this move (in a double sense).