To follow up on my post on 12/31, I watched the supervisor work with the chart she had for upgrades. She explained everything and showed me the chart. Basically, the closer your original room is to the upgrade, the less it costs for the upgrade. We had booked a 4c(family oceanview on deck 7) and were offered a Cat V(family sized concierge). There are only 2 levels -4b and 4a- between what we booked and the offered upgrade. That's why our upgrade was $1190. Had we originally booked an inside or porthole room, the same upgrade was significantly more. Since the Cat V was priced at nearly $23,000 just prior to our sailing, the extra $1190 WAS a deal!
Awhile back, someone had posted that port upgrades weren't what they used to be, but this poster was looking at an upgrade from an 11b to Cat T( one bedroom concierge) and was told it would be $4400. That makes a bit of sense due to the wide variance between what they booked and what they were offered. I'm sure time of year and other variables were in place, as well.