+1. Mike Fricker in a twitch stream said he was aware of the issue that adding new properties to a header or changing blueprint macros caused them to not show up on hot reload. This functionality has been improved, but not improved enough to not need to restart. I would love if hot reloading these changes was more supported.
As said in the title, when creating a new BlueprintNativeEvent (also BlueprintImplementableEvent) Hot Recompile isn’t enough for it to show up and so the Editor must be restarted for it to show up.
I hope you can fix this, as I was pretty annoyed thinking it didn’t work and I simply had to restart UE4… 
oh, thanks for letting me know
Hey -
As Allar mentioned, this is a known issue that is currently being looked into for the best solution. With the number of fixes being worked on it is difficult to give an exact time frame for when a fix is expected however it will be included in a future update to the engine.
Cheers