Hey ,
Yeah, I tried the Event Receive Execution Finish. Only it didn’t happen ;), seems its wasn’t called on the subtree nodes that were “subsumed”. I think it might work in your case because you’re running it on the executing node, where as I need to run it on the parent node (so that anywhere it needs to quit out of that subtree I should reset my value).
Unless Mieskzo fixed it and I’ve missed the fix 
which is pretty likely as I’ve not updated UE versions yet (I wanted to make sure I used the same versions for my tutorials rather than switching over mid-stream).
Maybe I’ll update when 4.6 comes out and is stable and update my tutorials a bit.
Looking forward to watching handle a stream
Phil.