We split our stay at AKL and the Poly on Jan.5-11 this year. The decorations were still up when we checked out of AKL on the 7th, and were up for the length of our stay at the Poly. We also were able to see the decorations at GF, CR, and YC. Oh, and some decorations were still up in the parks, as well. It was a real surprise and treat for us.
Hope you get to enjoy them for your stay!