On Wed, Mar 16, 2022 at 10:31 AM Owen DeLong via NANOG <nanog@nanog.org> wrote:

You’re right… Two changes to a single file in most cases:

1. Set the correct new timezone (e.g. MST for California).
2. Turn off the Daylight Stupid Time flag.

This doesn't work at all if you want to properly display times in the past.

If you are in the new PST, then the setting is PST, and the timezone file properly has the current state as ending in November 2023 and the new state taking effect in November 2023 and you get proper display of time before and after the change.

If you are in the new PST and set your timezone to MST then all times before November 2023 are displayed incorrectly.

Matthew Kaufman