Outdoor Camera Was Stuck on People Only Detection

One of my outdoor cameras looks out onto a road, and I've had it on "All Motion" for a couple months now, as I like to get motion events on passing cars etc. I also have it plugged in to the power cord so I never have to change the battery or mess with it at all. 

Recently though, without me having changed any settings at all, the Camera seemed like it switched to "People Only" detection. Cars would not be registered or animals etc. But anyone walking down the sidewalk would trigger an event like expected. 

I tried switching back and forth between "People" and "All Motion" to no effect, and then did a full reset/re-add to no change either. People only mode was still stuck on even though it was in "All Motion". 

Finally, I removed the battery without doing a reset (and while set to All Motion), and did this a couple times for good measure, and that seemed to fix it. Cars etc. were able to be registered once again and motion events fired as I would expect for the All Motion setting.

Curious if this is a known issue at all? As I previously stated, I did nothing to change settings on the Camera, all of sudden this seems to have happened without cause, and I can even pinpoint in my timeline when the switch happened. One moment cars just stopped being registered, and only people were captured from then on until I fixed it with the battery removal. Camera version in 1.12 btw.