Heat coming on at 3am, not scheduled

[GmaA]

I've had my thermostat for over a year, in the last couple months the heat is coming on at 3am to 75° (we set 66°-70° at the highest). I use my schedule so I've tried deleting the schedule and rebuilding it without resolution. I have gone as far as resetting the thermostat, uninstalling the app from my phone, still no resolution.  It does not show the event in the history. I'm completely at a loss, any suggestions would be greatly appreciated! 

[MsMadox]

I had similar issue. I found something called seasonal savings when thermostat take over and set up what thinks would be the best to save. In my case it was adding unnecessary schedules during the day. I switched it off completely and problem is solved.