dpatte <dpatte@relativedata.com> writes:
But I have yet to get a clear answer as to whether we can request modifications to backzone records even if they only affect pre1970 clocks, and whether we can add new backzones for regions that differ before 1970.
Obviously, I'm not Paul and can't give you an authoritative answer, but I have read the archives of this mailing list back to its inception and I see absolutely no reason to believe that you can't contribute modifications to backzone records or that those wouldn't be accepted. Other people certainly have contributed such entries in the past and they were accepted. For example, from just last year: https://mm.icann.org/pipermail/tz/2020-July/029167.html Or in 2019: https://mm.icann.org/pipermail/tz/2019-July/028276.html Or in 2017: https://mm.icann.org/pipermail/tz/2017-July/025167.html Of course, they would need to come with supporting references for why they are correct, and there are some time practices that aren't representable or are not reasonable to track, which might be exceptions. For instance, theory.html mentions: In particular, the tz database's LMT offsets should not be considered meaningful, and should not prompt creation of timezones merely because two locations differ in LMT or transitioned to standard time at different dates. so presumably that specific change would not be welcome. But in general, I see no reason why contributions to backzone would not be welcome. I just refreshed my memory by reading the thread in 2014 that originally introduced backzone and the clear intent at the time was, among other things, to capture such contributions, including by adding new zone identifiers when necessary. There does seem to be some reluctance expressed in theory.html to take on the full number of entries that would be required to fully express historical time, and I know there have been some ambiguous past discussions about this, but in practice I don't think this will be relevant. Given the long history of the project and past experience, I think we can predict with a fair amount of confidence that the number of people willing to research and contribute such entries will be modest and are unlikely to overwhelm the project with data. Anyway, obviously Paul (or Tim) would be canonical here; I'm just an observer. But my clear impression from reading the mailing list over the years is that the reason for the low volume of contributions to that data is lack of interest among contributors and the difficulty of the effort, not that the maintainers are declining such submissions. Few people care about such data enough to do the work to track it down and document it, but there doesn't seem to be any reluctance to incorporate it if someone does do that work and provides it in the form of a patch. (It obviously gets somewhat lower priority than changes to times after 1970 if multiple things are competing for maitnainer attention.) -- Russ Allbery (eagle@eyrie.org) <https://www.eyrie.org/~eagle/>