Just got back yesterday. We were there 12/30-1/2.
On 12/31, evening apps were out 5-8 (usually 5-7) and then desserts were out until 12 (they normally close up at 10).
For evening apps, they were carving Prime Rib (wasn't that great, TBH) and had a bit more variety than a typical night. The food overall was fine but I wasn't that in love with the offerings. But, it was a fun vibe and the lounge provides a great place to spend some time waiting until midnight.
On 12/31, there is a reserved section of the Poly beach with chairs that is just for CL guests, which is strictly enforced. They served champagne and hot chocolate to guests on the beach, and maybe something else? Note, I am not sure if this section was also reserved for CL guests for the 12/30 show.
All-in-all, Poly CL on NYE didn't disappoint. Location, location, location.
Happy to answer any questions!