We've had 3 rooms on Deck 5 Aft (one cruise for 2 people, 2 with 3 people). I think all the rooms had accommodations for 3 (2 twins and the fold-down couch). I can't verify that all the 5 Aft rooms are like this, though.
We had room 5000 on deck 5 and it slept 4. It was a cat 8 room with a large window. The rooms down the hall from us also slept 4 that I could tell and the SPH rooms also sleep 4.
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