I looks like the UE4 editor holds onto some files. I would recommend using the recompile c++ code button in the UE4 editor to recompile your c++ code if you have the UE4 editor open. That being said there are still only so many things that you can change and have the hot reload feature work right. For example, it doesn’t seem that you can change header files too much but you can change most of the functionality in a function. I have also noticed that you can’t really change the constructors and have things work right.