I can't say exactly when it started but for some reason my battery standby and usage time is the same no matter what i'm trying to do. I've tried the following: 1. Disabling wifi, BT and cellular data. 2. Disabling app background refresh. 3. Disabling location services. 4. Logging out of iCloud account. 5. Setting carrier manually. 6. Reset network settings. 7. Reset all settings. 8. Full restore. Nothing seems to work, and the iPhone keeps doing something in the background, even in flight mode where every connection is disabled. Any other suggestions, or something i might have missed?