Adventure deck question

When I move on from Burnt Offerings to Skinsaw Murders do I remove all the "1" cards before adding the next deck to the pool of cards or do I just keeping adding in the decks as I move from adventure to adventure?

You keep adding the decks, but read the Rise of the Runelords Adventure Path card carefully, as it tells you when you are supposed to remove cards.

Keep adding unless something tells you otherwise.

Hint: The "Rise of the Runelords Adventure Path card" is a relevant something ;)