The reason I'm wondering about specifically S-off being the culprit is due to the clause HTC includes at the beginning of phone setup.. 'regardless of your 'contact htc' option, your device is considered a test device so it doesn't matter what you choose, your phone will always talk to HTC' (paraphrased). If the phone is capturing and updating various testing metrics to HTC it's never really sleeping and constantly keeping a data connection alive (even if very little data is sent).
I'm attaching a screenshot of what really 'broke the camels back' (or however it goes..). I'm not sure why wifi is shown as being on, it is most definitely turned off from the drop down panel.
Less than 5H of the phone being off the charger, less than 30M of screen on time.. something is keeping it alive and I have no idea what. This is a fresh install, I wiped the phone (w/ no restore) 3 days earlier. Amazon, Plex, Chromecast and Netflix installed. (amazon downloaded an album i had purchased, but that's it)
I've never had good battery life, but this is now in abysmal territory.