What you described is exactly what I meant. I shouldn't have said trickle charge (float), but as you can see it always stays at 100% by topping up before it drops to 99%.
None of this dropping to 97% as you described.
It may actually do it in practice, but the software isn't showing it in the android battery indicator. But this isn't what we're discussing.
The OP was showing 96% in android after being on charge all night - this never happened to me on the SU6.
and it was turned off at the time.
The phones generally uses 3% overnight while not being used but with wifi etc on.