No, you can see from the deck plan that 8164 is a category 2, that it doesn't face aft, it faces starboard and has a normal size balcony. When we use the shorthand of "aft cabins" for Millie class ships, we're talking about the ones whose balconies overlook the stern.
The aft cabins on deck 8 are category 1, rooms 8170, 8172, 8176 and 8185 and category 3, rooms 8166, 8168, 8181 and 8183. There are equivalent rooms on decks 9 and 7. You can see from the drawings that the balconies are much larger. That's the key point.