My best estimate as to when it started would be last Nov. It may have been sooner. One thing is for sure. It really kicked in when the solar panel status line was added. One other observation is that about the same time, I noticed the night time view is not as bright as it use to be. It seemed to start when the motion settings changed on the phone.
I have one battery in eash of my Spotlight cams.
All four of the cams are struggling to maintain. Even the cam that has a south facing solar panel.