[tz] Yukon to move to year-round PDT

[Robert Elz]

    Date:        Sun, 8 Mar 2020 03:12:57 +0000
    From:        Chris Walton <Chris.Walton at telus.com>
    Message-ID:  <8d0180be1f9648b09103043e21b0195a at BTWP000240.corp.ads>

  | Yukon Standard Time (YST) is officially UTC-9 as defined in section 35
  | of the Canada's federal Interpretation Act.

According to that, that is unless it has been modified by a
proclamation by the Govenor in Council (and since Yukon apparantly
hasn't been using UTC-9 for some time, I'd suspect that has
probably happened).

But that act doesn't mention "YST" at all, nor does it in any
way prevent anyone from using that abbreviation (or acronym, or
whatever it is really called) for any purpose, with any meaning
they like.   If I want to use it to mean Young Sexy Thing there's
nothing there to stop me.

So:
  | YST cannot be arbitrarily redefined to UTC-7 by anybody on
  | this mailing list;

Of course it can, we can use whatever abbreviation that we consider
appropriate.   I have no opinion on what that should be, I'm nowhere
near Canada, but there is absolutely nothing there that requires or
prohibits anyone from doing anything at all - it is simply an interpretation
act, which specifies what certain phrases mean when used in other acts
(in this case "standard time").

  | nor can it be redefined by the Yukon government.

Whether it is within their (current) power to choose the time in
which they operate I have no idea, but there is certainly nothing
in that act which prohibits them from doing anything they like.

Whether they have the ability to alter what standard time means
for the purposes of federal (Canadian) acts & proclomations, I have
no idea - that could have been delegated to them by some other
instrument, or not.   But there's nothing in that particular act
which limits whatever powers the provinces & territories might have
to legislate with respect to how time should be counted for the purposes
of those matters that are under their control.   Whether there is
something elsewhere, I have no idea - I have never bothered to research
how the Canadian legislative system works.

But if the Yukon territory shifts its clocks to UTC-7 year round, then
I'd expect (if still required) a procolamation from the Govenor in Council
stating that would be issued (unless for some obscure reason some other
part of Canada actually cares what the clocks in the Yukon say, which
frankly, I doubt).

  | Furthermore, I think that redefining YST is a bad idea because it
  | would create ambiguity

The three(or whatever) letter TZ abbreviations are inherently ambiguous.
Anyone who ever attempts to use them for any purpose whatever, other than
giving a warm fuzzy feeling to humans deserves no sympathy at all when
whatever they are doing fails miserably.

  | when dealing with old and new time stamps.

When dealing with time stamps, we know what the offset from UTC
was from the date/time recorded, if we know in which timezone the
timestamp applies (for which the abbreviation is not sufficient).
That's what this project's data is all about, and why we collect
all that historic information (rather than relying upon something
deficient like a POSIX TZ string).

I understand that people have fixed opinions on what particular timezones
should be called, and what offset from UTC they should represent, but
things change - none of this has existed for very long (archeologically
speaking) and what we consider to be something fixed and unchangeable today
might be entirely different tomorrow.   PST might become UTC-7, YST might
become UTC-7 as well - that we used to believe they were UTC-8 and UTC-9
respectively means nothing at all.

kre