If it's false reporting then it's causing me to go from 7-9 on screen time to 3 hours while using the exact same settings I used on jb. My reported usage wasn't 5%. It was 18%. Cell idle battery usage went all the way up to 16%. Back on 4.2.2 and currently am at 70% and 3hrs and 30mins screen on time. In my case I'd say it's more than false reporting.
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