I wish the power circuit can be improved so the PBP will not draw power from the battery while the PBP is connected to the A/C adapter.
Mine PBP keeps drawing power from the battery when I have the A/C connected. And eventually use up all the power from the battery.
It takes more than half a day to charge the battery too.
The latest production run (2022) doesn't seem to have this problem. Mine will charge when I'm using it full-bore.
I wonder if your battery or power supply are different. None of mine take that long to charge.
I never turn mine off. None of them. My wife uses one with Manjaru. I run NetBSD, and on the older one I use estd to throttle the CPU usage. These days I run VICE on it almost exclusively. I usually get 6 or 7 hours of use on battery and then charge it for a couple of hours. The other one, which I received a couple of months ago also runs NetBSD. I was able to compile several large pkgsrc packages with the CPUs running full bore for several days and the battery never went below 100%, which surprised me. I use it pretty regularly for web browsing, and remotely controlling several other machines with VNC. I don't even think about the battery in it. Whatever changed with the new hardware design is amazing in this regard.
I won't be home to do much testing for probably over a month. When I do get time at home, time will be precious. Else I'll be happy to help.