My Debian host has the correct time and time zone, but the Time Zone under System Settings in ERPNext continues to display America/Los_Angeles. Here is what the host reports.
Local time: Mon 2023-03-13 21:49:14 MDT
Universal time: Tue 2023-03-14 03:49:14 UTC
RTC time: Tue 2023-03-14 03:49:14
Time zone: US/Mountain (MDT, -0600)
System clock synchronized: yes
NTP service: active
RTC in local TZ: no
This does not appear to be a modifiable field. Documentation for my version (14) states, “Time Zone: Sets time automatically based on the time zone.” While this is not entirely clear, I believe it is referring to the time zone of the underlying OS.
I have also checked the time zone specified for the user is correct.