For a British Isles Cruise in August of next year, I currently have a balcony stateroom (BA) and really wanted a mini suite when I initially booked (don't ask me why I didn't just book it then, because I don't have a good excuse).
When we first booked, it was on the Emerald Princess and we chose our room. For whatever reason, Princess changed it to the Regal Princess and now we have a guarantee cabin (BA), still to be assigned. When I looked at mini suites (category MA), I found that I could upgrade now for $600 total (Club Class was not an option when I did a mock booking).
If I understand the bidding correctly, I would have to wait until we were 85 days from sailing. My only concern is that a mini suite won't be available to upgrade to, otherwise I wouldn't worry about waiting.
Assuming you wanted to upgrade to a mini suite, would you do it now or wait until you could bid on an upgrade?