This has happened to me enough times that its worth mentioning....
I'm running a map with a healer as my leader using the autospin feature battling a panzer or level where I know I don't need to worry about getting killed. I get out of the DE app to use another app on my phone real quick. When I go back in I see that autospin picks right up where it left off, only this time my healer leader's skill isn't working and find I was killed. I've spent gems and revives as a result of this in each of these occasions.