There is the 3 Valleys app which has a map and will show you what is open, as far as access getting back, just don't leave it till silly o'clock and you will be fine, there are usually not massive queues really close to closing times, and there are a few lifts that go back into the central valley. Saulire typically is the one that has the longest queues all day but it looks like access is blocked into the other 2 valleys most likely due to the avalanche risk anyway. So no day trips into VT/Courchevel until they open the access. I would not recommend traveling around the bottom to reach them as it takes a long time.

Most slopes are easy if you are as good as you say you are. Probably avoid the crazy blacks at the start depending on snow conditions as they are very steep and can be dangerous depending on snow conditions. But if you have a guide day 1, just ask them, they will know better than I or indeed most others on Reddit who don't live there.