Chapter 9 was the big capstone event for the story so far and the resolution to the DIKs mansion getting trashed. Halloween is also one of the biggest party holidays in the US, and very likely the biggest one celebrated by college students. So it kind of makes sense for almost an entire chapter to be dedicated to the party alone.
I think that chapter 10 will primarily be story focused, with the Thanksgiving party being the finish to the chapter, with maybe Fuckface and his LI having a short scene with his father after the party. Thanksgiving, while being an important holiday in the US, isn't really a big "party" holiday, unlike Halloween. Stands to reason that it might not have as involved a free roam event this time around. I honestly think we'll likely see a scene / short free roam each week between Halloween and Thanksgiving.
The biggest storyline scenes I'm expecting to happen in the three weeks are Jill / Bella talking, especially if on Bella's route and another step in the Josy / Maya storyline. Smaller story beats that I'm expecting is Riona / Quinn / Lilly having some form of confrontation, and Sage's first kinky whatever with fuckface. I think we can hold off one more chapter on the Jade storyline for Sage.