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

[Max Nikulin]

On 17/01/2023 16:45, Tim Cross wrote:
> Ihor Radchenko <yantar92@posteo.net> writes:
>
> > Tim Cross <theophilusx@gmail.com> writes:
> >
> > > It also seems that the solution will need some mechanism (possibly on a
> > > per time stamp basis) for the user to specify what should happen when
> > > either the time zone has a daylight savings transition, when the
> > > timezone rules change or when the user's 'default' time zone changes
> > > because they have changed locations.
> >
> > Could you please elaborate here?
>
> I have some meetings scheduled in my org files which show up in the
> agenda.
>
> Meeting 1 is a reoccurring meeting which happens every 2 weeks.
> When we
> transition into/out of daylight savings time, I don't want the timestamp
> to change. THe meeting will remain at 3pm.

You specify time zone (globally, for the file, for the subtree, or for 
the particular timestamp) using IANA ID (e.g. Australia/Canberra)

TZ=Australia/Canberra date -d "15:00" '+%F %a %T %z %Z'
2023-01-19 Thu 15:00:00 +1100 AEDT

TZ=Australia/Canberra date -d "+6 month 15:00" '+%F %a %T %z %Z'
2023-07-19 Wed 15:00:00 +1000 AEST

> Meeting 2. This is also a reoccuring meeting. However, this meeting is
> with people from a number of idfferent time zones. When my timezone
> moves into or out of daylight savings time, I need the meeting time to
> be updated - moved forward/back 1 hour.

You either specify time offset or a timezone with fixed offset

TZ=Australia/Canberra date -d "09:00 +0500" '+%F %a %T %z %Z'
2023-01-19 Thu 15:00:00 +1100 AEDT

TZ=Australia/Canberra date -d "+6month 09:00 +0500" '+%F %a %T %z %Z'
2023-07-19 Wed 14:00:00 +1000 AEST

TZ=Australia/Canberra date -d 'TZ="Etc/GMT-5" 09:00' '+%F %a %T %z %Z'
2023-01-18 Wed 15:00:00 +1100 AEDT

TZ=Australia/Canberra date -d 'TZ="Etc/GMT-5" +6month 09:00' '+%F %a %T 
%z %Z'
2023-07-18 Tue 14:00:00 +1000 AEST

> Next week, I'm travelling to a different city for work and will be in a
> different timezone. I need all my meetings to be adjusted except for
> those I've already booked that are in the timezone I willl be in while
> I'm away.

You specify that you original time zone e.g. Australia/Canberra, since 
2023-01-25 15:00 +0100 Europe/Berlin should be used and that agenda 
should be presented in either the "time zome" following you, or some 
fixed one (Australia/Canberra, Europe/Berlin, or Asia/Singapore)