OK … so what was the deal with Arya and Sansa?
Option 1) They were playing Littlefinger the whole time, which means they staged all their interactions over the past couple of episodes, including behind a closed door when Arya threatened Sansa with a dagger. Were they confident that Littlefinger was lurking in the hallway, listening in? It just doesn’t make much sense in the way it was staged. Also, why all the elaborate shenanigans? If Bran brought them all up to speed at some point several episodes ago, why mess around? What did that accomplish? Just arrest him. Kill him. Whatever. It’s not like they got him to reveal his guilt to the other lords. And why send away Brienne?
Option 2) At some point in the late-game, perhaps after Littlefinger’s “I assume the worst” speech, they figured things out. Maybe they asked Bran “Hey, what’s up with Littlefinger?”. This is an awful option because it means their terrible interactions this season were genuine. Also, it means they went from Arya threatening to cut off Sansa’s face to having their “Sisters 4ever” moment up on the parapets not long after.
I liked where it ended up, and I thought that’s where they were heading when this all started, but it’s all just clumsy.