And also AFAIK, you cannot upgrade a
free dining pin/code/offer to Premium or Platinum.
equinoxman: you are booking a 1 night premium and paying for 1 day base tickets. On your 2nd res, since you add dining, you are also paying for 1 day base tickets again. If you book premium plan it has to be used on day1 and 2 cant combine premium and deluxe dineing into 1 ressie.
I'd extend the initial ones, specially if you take tours and stuff inside the parks on arrival AND departure days. Make sure your 2nd rez is for 1 day base only...