In the Kindle case, we rely entirely on the system, so I'm going to chuck that one in the generic "Kindle FW doing weird crap in the BG" bin

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I haven't seen anything weird on the Forma (which should be similar to the Clara, as far as this is concerned) as far as sleep is concerned, but I'm not a good test-case on that front, as I barely ever let the device sleep outside of Nickel.