Re: [FEATURE REQUEST] Timezone support in org-mode datestamps and org-agenda

[Thomas S. Dye]

Aloha Max,

Max Nikulin <manikulin@gmail.com> writes:

> On 20/01/2023 15:17, Tim Cross wrote:
> > So far, nobody has shown any reason why using UTC to 
> > distinguish the
> > case where the times need to be adjusted and local tz when they 
> > don't
> > won't work a a  mechanism that can be used to allow org to 
> > handle things
> > better than it does now.
>
> Let's try to move in small steps. UTC as storage format.
>
> An issue with events scheduled as local time in some particular 
> timezone (not
> your current one) and stored as UTC timestamp when IANA tzdata 
> is updated to use
> new timezone offset:
>
> https://codeblog.jonskeet.uk/2019/03/27/storing-utc-is-not-a-silver-bullet/
> Storing UTC is not a silver bullet
>
> Do you think it should be ignored? I faced such issue.

Good example!  Thanks for the link.

Note that the problem of arbitrary change of a timezone's relation 
to UTC might be handled differently for occurrences and events.

The blog example is 9AM in Amsterdam at a date some years in the 
future.  Because the example includes a place, it refers to 
space/time, and is an event (not an occurrence).  Now, if 
Amsterdam's timezone arbitrarily changes its relation to UTC 
before the conference takes place, then everyone who participates 
in the conference must notice this (or miss the start of the 
conference).

Let's consider an occurrence.  A virtual conference is organized 
by someone in Amsterdam, who sets a start time corresponding to 
9AM in Amsterdam at a date some years in the future and invites 
participants from all over the world.  Now, if Amsterdam's 
timezone arbitrarily changes its relation to UTC before the 
conference takes place, then must everyone notice this?  Or, 
should Org, from the time the arbitrary change is made public, 
simply adjust the conference time for all the participants in the 
Amsterdam timezone?  The latter makes sense to me--all the 
participants in Amsterdam will be aware of the arbitrary change, 
so will not be surprised when Org calculates a different start 
time. Such a change would almost certainly confuse participants 
unaware of the arbitrary change in Amsterdam timezone.

hth,
Tom



--
Thomas S. Dye
https://tsdye.online/tsdye