Alas it appears, using a from-source build of UE4, that all this now does is generate the UE4.sln used for building the editor itself, it doesn’t seem to generate the project for the supplied uproject 
Alas it appears, using a from-source build of UE4, that all this now does is generate the UE4.sln used for building the editor itself, it doesn’t seem to generate the project for the supplied uproject