IIRC that is near the pad that formerly housed the Mystery Machine and Snoopy's doghouse. If it's specifically where the gap in the trees is then it's right where the original Phantom Theater entrance was.
It's entirely possible that this could be 1) an extended queue, 2) stroller parking, or 3) a path/curb replacement. I'd be happy to see some new concrete on the plaza. Any extended queue would need to find a good way to navigate the hill and get back to the facade, so I'm thinking it's either stroller parking or concrete replacement. For all we know there could already be facade work happening on the lower areas of the building. The only signs of painting we're likely to see is some scaffolding. The bridge, "gate", and giant mouth at the entrance could also be worked on without the webcam seeing due to how the top of the castle blocks them.
For concrete work (seen from this distance/video quality) you will generally be able to observe three stages:
Breaking up/removal of the existing concrete. (rough ground)
Framing of the new concrete. (lumber boundaries)
Pouring/finishing of the new concrete. (you'll see the truck/wheel barrows)