Thanks all for the info. As I said, we're happy with our cabin choice, and are not looking for an upgrade. However, I was curious as to how the upgrading works. As I understand it--when booking, I can book a guarantee Cat H (or whatever), pay for Cat H, but there's a possibility that I may be upgraded when checking in with no additional cost, right? If I book a particular cabin, then RSSC won't change it without contacting my TA or me. And I always have the option of paying for an upgrade, if one is available. Fair enough.

Thanks again,
Deb