Those of us who pay attention know that
GameGrumps doesn't affect JonTronShow. They record GG once a week, and Barry does the editing.
Jon has a girlfriend, though, and
he could have left to live with her in NYC.
Jon also has had
some sort of problem with The Game Station, which GameGrumps is a part of.
The strange thing is that if Jon and Arin knew beforehand what was going to happen, it seems they would've told people about it prior to changing everything. Some things like SteamTrain were obviously planned, but Jon seems to be in a different location in
Ode to Jon, which is suspicious. Why wouldn't they have recorded it beforehand, everyone at the same location, if it was planned?
It's as if some big thing happened that made Jon suddenly leave, and they're just trying to play it off as Jon focusing on his own show, instead of telling the whole truth.