[tz] Antarctic research base Vostok local time

Brooks Harris brooks at edlmax.com
Tue Dec 19 07:51:42 UTC 2023

On 12/18/2023 5:35 PM, Paul Eggert via tz wrote:
> On 12/17/23 07:00, АПС АКУЛОВ via tz wrote:
>> Pse be informed that from December, 18, 2023 00:00 by my decision the 
>> local time of the Antarctic research base Vostok will correspond to 
>> UTC+5.
> Thank you for the information. Do you have a public announcement on 
> the web, or some other source, that we can cite?
> Does "00:00" mean 00:00 local time, or 00:00 UTC?
> Has local time at Vostok been UTC+6 ever since 1957, or has it changed 
> before?
> I ask these questions because any TZDB changes will be after the fact, 
> so we can take the time to be careful about the changes. (Please see 
> [1] for why it's better to give advance notice about changes like this.)
> Thanks.
> [1]: https://data.iana.org/time-zones/tz-link.html#coordinating

In my opinion the fact that it takes a long time for TzDb data to 
propagate to downstream systems is an extremely important fact that is 
not recognized by all 'policy makers' and it should be to help avoid 
difficult consequences. I feel this fact is buried in TzDb documentation.

"...any rule change should be promulgated at least a year before it 
affects how clocks operate; otherwise, there is a good chance that many 
clocks will be wrong due to delays in propagating updates...".

It's easy to imagine computer stuff updates almost immediately like it 
seems to on the internet, but local time updates do not work like that.

I think an explanation of this fact should be front and center at TzDb, 
indeed, perhaps the very first thing on the main TzDb page: 


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