This morning, my phone grew very warm and the battery took a major hit. When I was trying to figure out what the offender was, I looked at the "About phone" screen and saw a heading "Factory data reset" with today's date, 8/20/2015. I haven't done any kind of reset, and, in fact, the same screen says that my phone has been up for 625 hours. All of my data and apps seem to still be on the phone, so I don't believe there's been a factory reset in the commonly understood sense. Does anyone know what this is?
Path to the screen in question: Settings -> About phone -> Status
Phone is a Samsung Galaxy S3 mini (SCH-I435), Android version 4.4.2.
Thanks!