"Mark Davis" <mark.davis@jtcsv.com> writes:
There are at least two choices:
1. America/New_York will always be the timezone for the city of New York, even if it secedes from the US, joins Canada, and goes on Newfoundland time.
That's correct.
2. America/New_York is a stand-in for US Eastern Time. If New York City secedes and changes, the America/New_York TZID will associated with US Eastern Time.
No, America/New_York is intended to be New York time.
And if America/New_York is to be stable, that would, of course, be a huge mistake,
That's what the 'backward' file is for. For example, when we discovered that the name "Ulaanbaatar" had become far more common in English than "Ulan Bator", we renamed Asia/Ulan_Bator to Asia/Ulaanbaatar and put a link in the "backward" file. This sort of thing happens occasionally, just as ISO 3166 renames country codes.
they have to have a clear meaning so that when the "facts on ground" change, one can have reasonable expectations as to what principles would be maintained in adjusting the TZIDs to the new circumstances.
This issue is discussed at length in the Theory file.