May sound funny but I think it would be really cool if there was an "on collision ended" event. It would save so much time!
"Is not overalpping" + "Trigger Once" works nice though in many cases it triggers not once per action but once per session.
"Is not overlapping" + playing with variables helps but not always. Maybe I don't know or understand something yet.
What do you think about such feature - do we need it?