Well after the battle lord manderly arrives and gives his big speech like in the books. With manderlys support + the vale Jon has the numbers and I’m guessing the other houses see it that way and kneel. Plus he has Sansas support(the true stark heir as rickon dies beginning of battle and bran is presumed dead(even though he’s not). That’s all I know as far as north storyline spoilers-wise. Truede posted today saying episode 9 is 2 locations, winterfell and mereen (we get to see 3 dragons!). Also house Tyrell is pretty much killed off this season and tommen dies jumping out a window (most think it’s related to cersie setting the sept on fire or w/e) if you want to know more look at the free folk sub Reddit, they know their shit.