Must be from season 3, I guess.
Not really sure, but it's probably like S03E07, something around there
That being said, a few questions I don't think they will address either are:
The Hapstalls: Did Caleb really killed himself? What happened to Philip? Will they ever address Catherine's innocence and being in jail because of them?
The Mahoneys: What did Sylvia meant when she told Annalise "You're wrong about so much"?
Eggs 911: What Happened to Levi? Is he still in jail? Don't they even feel guilty? (At least the ones who know the truth: Frank and Annalise)
Others we can take for granted are:
Did Frank really killed Wallace Mahoney? (Just cause we never saw any evidence, but it's pretty certain)
Did Caleb really killed his parents or was it Philip? (Seems like it was Caleb, but again: we never saw it)
Somethings I think (wish) might come back:
Hannah Keating looking for justice.
The Campus officer who caught the K4 walking out of Annalise's house with Sam's body in a carpet.
Connor's car. (where they transported the body)
Anything that could lead to the FBI finding some proof about the crimes.
I think the Who Killed Wes it's not a question anymore, they showed it was Dominic by the direct order of Jorge. I don't think they will address that since it was pretty much answered.