My wife and I boarded last week around 1:30 (that's when the bus got us to the terminal), and by the time we got on board the only ressies left were for the first night, 7 or 7:30 pm. They were telling us the dress codes for the first night were sort of relaxed, but I was determined to wear the tux I had rented. It was a great meal, and the server brought us a cake for our 20th anniversary (and also wrapped it up as a foil swan so we could take it back to the stateroom).
We checked back in later and found that there were openings for the 4th night, so we went ahead and booked another night and asked for the same server (Louise). She was great, and we had another great dinner there. My wife would have liked to have had high tea also, but that never seemed to open up.
The funny side note is that we were wondering if our future dining mates were wondering where/who we were when we didn't show up the first night. When we finally met the other two couples the second night, we discovered that one of the other couples was ALSO dining at Palo's the first night right behind us!