Mrs O,
My apologies, I thought you were one of the beta testers for some reason. Maybe I read something in your posts regarding side loaded firmware and got that impression once upon a time.
At any rate, with Kobo we're all Paying Gamma-Testers...
OTOH, I could think of worse things as long as they're willing to continue upgrading firmware and introducing new features for the rest of the product line, not just the latest models.
I'm 24 full days in since charging, 44.5 hours of reading on lowest lighting level, and at 22%...
The last 4 hours of reading/three days of sleep have dropped the battery meter considerably, but linearity, or lack of, may play a large role there. I'm probably off the plateau and on the far right highly sloped part of the typical discharge curve. I'll be glad to finish, but pretty happy with overall battery life if it gets anywhere near 50 hours with the light on and 21 days of sleeping. I can only imagine that it'll do better if I go back to shutting it down in between, at least for my usage pattern, but perhaps the self discharge is nearer the sleep mode penalty than I'd thought. Frankly, I'd have been happy getting 2 weeks between charges with the lighting on low and maybe 2 to 3 hours a day reading.
Well, it finally quit. Last % I noticed on it was 5%, so not so bad in terms of indicating it was nearly out. At 8% I noticed a message on the top line of the display that said something to the effect that the battery was low and should be charged soon, probably would have been displayed from 10% down as a guess.
My final numbers would be 24 full days and ~4 hours in since charging, ~46.5 hours of reading on lowest lighting level, and shut down shortly after I saw it was at 5%...
That's almost two full 24 hour days of reading time, plus ~22 full days of sleep mode on one charge -with the LED lighting on low the whole time! I'm more than satisfied at that considering that with being able to shut it off in between reading sessions it should go even further. I hope this helped provide a baseline for what others might expect.