Not sure, but it might be related to what I wrote in another thread of mine relating to a strange “over-counted power use” item in battery statistics.
Your drop is really heavy on the other hand. What I see, is that once I load to 100% and do nothing is it linearly or if shut off immediately dropping to around 95%. This is nothing astonishing as you need to be aware of the fact the 100% is just fake. No system really loads a Lithium battery to 100%, this would strongly affect its lifetime. But to make customers happy they pretend it was 100%. Since they need to recover to reality once in time, you often see either (fake) linear deloading curves or sudden deloading jumps to the real value it was, while you have done nothing on the system to consume power.
But a deloading with such strong jump you have might be more another, maybe hardware issue.
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