Not being real scientific here but that’s it with 3-4 hours of streaming calls on Zoom or Teams.
I read somewhere that Phonaks use 1 side or the other to do the heavy lifting of the Bluetooth, your AuD can change it from 1 side to the other to balance things out a bit with the ear that draws less, if that is the case in your situation.
You can see which one is the Primary in your Bluetooth settings, you’ll see 1 LE_R and 1 LE_L and then 1 more either Left or Right Phonak Hearing Aid, that’s the Primary.
Your Left ear looks worse to me so in your case the Primary should be on the RT assuming your Left draws more current, which I think it would.
It only makes sense that driving a speaker harder would draw more power.
Same goes for P vs UP receivers.