Originally Posted by orbitmic

Well, yes, I suspect it did matter As a matter of course, FAs would be very reluctant to let passengers come up to the upper deck - especially from Y which I suspect, by law of numbers alone, is where the majority of requests will come from. "Resident" passengers would probably not appreciate having people coming to visit the surroundings while they rest or eat, and the FAs would probably not want one of them to complain. As others have mentioned, if you are curious about what the upper deck looks like, the right thing to do (both in terms of not putting the FAs in an awkward situation, not imposing on the people sitting on the cabin, and maximising your chances not only to visit the place but even to take photos, see what the seats are like etc) is to wait till the end of disembarkation and after the upper deck cabin has been emptied, ask if you might go up and take a sneaky look. I'm pretty sure they would say yes at that particular time.