- and 3. are compatible changes. 1. however, isn’t. You’ll still be able to open it in vanilla UE5.6, the lightmap UVs will however be generated using the latest one coming with 5.6 though. The lightmaps will come broken, yet can be fixed with one lighting build.
Also, if you’re not using any Level Instances but get 2 and 3 right after 1, please redownload the patch as I fixed an issue which is a conflict between them.