Descent G1 battery time remaining bug

I think I found a bug with the Garmin Descent G1 solar and the battery time remaining. Lets say the current battery time remaining is 27 days. If I perform an activity such as strength training for 30 minutes, on completion the battery bar will be about the same however the time remaining will drop to around 8 days, almost like it's used most of the battery. If I enter dive mode and exit again, the battery will update to around 27 days again. No other settings are changed.

Anyone else found this? I'd honestly prefer a battery percentage data field on the watch face, but time remaining seems to be the only one available, which annoyingly seems to jump around.

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