We were on the 9/1 4-night Dream sailing as well. We stayed at the Hyatt MCO the night before embarkation and were on the first bus to port. We were in the terminal by about 10:10 and were the first ones at the supervisor's desk. DH and I were celebrating our anniversary and were hoping to upgrade to Concierge, so we only asked about cat V and T. We were also quoted $700 for a V and $1,100 for a T. Based on what I had read here I was expecting that price for the V, but the T was a less than I had expected (it's all relative, of course!). We went ahead and splurged on the T. We got the last one on deck 12, but there were several others on deck 11. As of 3 days before sail date, the
DCL web site had been showing only 1 cat V and 5 cat T. I'm guessing that a couple of people who had booked cat V upgraded at port to cat T.
I asked the CM at the supervisor's desk a few questions about the pricing chart. She confirmed that the chart is produced before each cruise and that it does vary based on certain factors (she was very vague about what those factors are). DH and I speculated that the difference in price between a V and a T may have been smaller than usual because there were 5 available. Like LocaRoja, we had an absolutely amazing time and were very impressed with the service and perks in concierge. I'll be starting a trip report soon and will detail our experience there.
ETA: We had booked a cat 7A under the DRM promotion, which was $599/person for DH and me + a $100 OBC. We had been assigned a 5A at about 52 days out. The CM asked us for our room number when we got to the supervisor's desk. I'm not sure whether the price she quoted us was for an upgrade from 7A to T or from 5A to T. I know that in theory the cost is supposed to be based on the category you booked, but I did not confirm what category she used as her starting point.