You may want to post this question on either the HAL board or the Community Message Board. I don't know anything about upgrades, but I remember some of the reasoning behind them (not sure if I got this info here or from my TA) but the cheaper rooms tend to sell out first and that is what the cruise line wants to advertise, but if all the cheapest rooms are sold out, they may upgrade others so that they have more lower price cabins to sell.
Is your room a guarantee? I think when you book a guarantee, you are guaranteed to get the minimum in that category. We picked our room out already since I got sick on the first cruise, so I could be in a more stable area.
I know that sometimes when you have a guarantee you risk maybe being near the elevators (bad if you go to bed early) or near the anchor...which I hear is pretty loud.
But like I said, I really have no idea at all but I'm sure that someone here can answer your question.
See you on the Z!
