On Dec 12, 2024, at 8:46 AM, Brian Park via tz <tz@iana.org> wrote:
One thing rarely mentioned in these discussions is the millions of electronic devices (e.g. timers, clocks, watches, thermostats, etc) which are hardcoded to handle DST using the current US/Canada rules (i.e. first Sunday in Nov, second Sunday in Mar). If the DST rules are changed, those devices will become obsolete because the firmware for those things will never be updated.
So do they sell special models in Arizona (along with the regular model, for residents of the Navajo Nation)?
Or do they have, for example, a switch that controls whether to observe DST or not?