I’m working on a old Android tablet running 5.1, and the timezone is fixed to Eastern time. I have root/adb access, but not sure how to safely. The setting is disabled in GUI. I only found some instructions over 12 years old on how do this (adb shell) but not thorough enough that i felt confident to follow.

I tried setting the time manually, but everytime it connects to the internet (over a reverse USB tether) it resets based on the set timezone (which makes sense, since this would break encryption: https, ssh, etc). This is with “set time automatically” disabled, so it appears i need to adjust the devices set timezone.