very funny things happen when there is a shared physical resource e.g. a booked meeting room, and you have a bunch of people schedule meetings with different reference time zones.
ah, and if you think this creates havoc only for a the few weeks while the TZs are out of sync, remember that in the southern hemisphere DST is applied in "reverse"
In my country the train stops for one hour at the spring DST change and just waits for time to pass to account for the "missing" hour and not mess up the schedules by arriving one hour earlier.
It's also interesting that since this doesn't happen frequently enough it's usually hard to develop a good way to get out of it.
"The timezone you have used to define this booking has been altered, and the booking cannot be updated due to unavailability of the resource XXXX. Please choose a new time for this booking."
Heheh, exactly. We're currently debating how best to implement this since this one is more a UI issue than a UTC/Time issue.
For example if the user wants to schedule a call at 2pm New York time (UTC-4) we need to show them the consequences of dialling a participant in the UK (UTC+1) and even more so someone in Sydney (UTC+10).
If you use your ZonedDateTime classes carefully in your code (or equivalents if not using Java) then your app does take care of the DST changes. You can then show the user the scheduled time for not just the person making the creating the event but for every participant - ultimately the user has to decide what compromise to make when scheduling events across time zones and DST changes.
My side doesn't observe DST. The other side does. The border keeps different Summer and Winter hours.
Trying to figure out when I need to leave to make sure I get to the border during its open hours to get through, and then when I need to leave (in local time on the other side) to get back through during the open hours is an extremely tedious problem.
Worst part is crossing the border is just me driving South. My longitude doesn't really change.
When I say "becomes a lot of fun" what I actually mean is that this observation lets us understand very quickly that the problem is not generally solvable. One way or another, somebody's 9 o'clock meeting is going to suddenly take place at 10. Having accepted that, we can push through the idealism and start working actual solutions like the one you described - have the user attach the regularly scheduled meeting time specifically to the UK or to the US.