I might not be understanding your question correctly but here's my initial answer:
Checking in at the hotel is a lot less hassle than checking in at the port. I heard you can do it simultaneously when you actually check in at the hotel, but when I did the land/sea, I had to go to a separate cruise line desk where they took all the documents, etc. It was still a lot easier because I could do it just about any time during the land stay and there was never any line.
Not sure when/how the dinner rotation is assigned, but when I did the 7-day, the rotation was printed on my Key to the World card. I don't remember if they printed it on my card when I did the land/sea, but the same card accesses both your hotel room and ship cabin. So it's possible the rotation will be printed on there and you can see it as soon as you check in at the hotel and get your card (someone who has done this more recently can verify for certain).
You can't make Palo reservations until you board the ship. By then you should know your dinner rotation and which night you are assigned to PC.
Sorry if this isn't quite the info you needed, but thought I'd give it a try.