Well, just try. 
It takes longer to write a post about it.
But even with this unload-complete code snippet I’m pretty sure you want, or may even have to add a 1-frame delay so that you’re not loading in new content while unloaded scene’s objects may not have been fully removed from memory. This could increase memory pressure.
I’m not sure whether unload will be considered complete when the scene’s objects are merely scheduled for destroy at the end of the frame, or whether it will actually wait until the next frame.