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DST offset apparently not accurate

  • 2 (ردّان اثنان)
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  • 3 views
  • آخر ردّ كتبه compass_drg

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DST just kicked in for Eastern Australia, I noticed that the timed calendar events for the day were reporting inaccurately.

The Win 10 OS automatically changed the time according to time-zone. Australia/Sydney changed from GST+10 to GST+11. With Thunderbird Calendar set for Australia/Sydney, and the Time being just after around 10:10 the events from around an hour prior are displayed a little inaccurately. An event at 09:11 is displayed as 08:11 in the 1 Day View (screen-shot supplied) The same event is displayed as 09:11 in the Agenda View (screen-shot supplied) as reported as current, with the following event reported as occurring in the future.

By changing Thunderbird's time-zone to Australia/Brisbane, which is still at GST+10, the agenda view at least returns to expected behaviour. The times of the events remain correct, but there refer to the past, not future.

The other calendar views, Day/Week/Multi-week/Month still report the events as in the 08 hour. But as I mainly use the agenda side view, this is less of a confusing display issue.

The third screen shot showing the Multi-week and Agenda views together illustrate the same event with two different times. That in itself strikes me odd that the same data can have two different values.

The 2 events illustrated were created in Thunderbird in the 09 hour.

… prior to this post, I applied the most recent update to Thunderbird, just in case.

DST just kicked in for Eastern Australia, I noticed that the timed calendar events for the day were reporting inaccurately. The Win 10 OS automatically changed the time according to time-zone. Australia/Sydney changed from GST+10 to GST+11. With Thunderbird Calendar set for Australia/Sydney, and the Time being just after around 10:10 the events from around an hour prior are displayed a little inaccurately. An event at 09:11 is displayed as 08:11 in the 1 Day View (screen-shot supplied) The same event is displayed as 09:11 in the Agenda View (screen-shot supplied) as reported as current, with the following event reported as occurring in the future. By changing Thunderbird's time-zone to Australia/Brisbane, which is still at GST+10, the agenda view at least returns to expected behaviour. The times of the events remain correct, but there refer to the past, not future. The other calendar views, Day/Week/Multi-week/Month still report the events as in the 08 hour. But as I mainly use the agenda side view, this is less of a confusing display issue. The third screen shot showing the Multi-week and Agenda views together illustrate the same event with two different times. That in itself strikes me odd that the same data can have two different values. The 2 events illustrated were created in Thunderbird in the 09 hour. … prior to this post, I applied the most recent update to Thunderbird, just in case.
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The more I try to compensate for this issue, it ends up in more of a mess, especially since the Calendar syncs to my mobile. So I have reset the settings back to Australia/Sydney and will have to deal with the erroneous looking calendar display within Thunderbird.

At 12:10, I created a "Test Event" for 13:00 to 14:00 in Australia/Sydney time zone on Thunderbird As at around 12:30 On the Agenda view, it reads as 13:00 - in 90 minutes / obviously it should say "in 30 minutes" On the Day view, the event block is positioned at 12:00 to 13:00 On Google calendar (and mobile), the event is 13:00 to 14:00

Because of the mess from different time zones, I re-edited all of the events from earlier, outside of Thunderbird; So in the Agenda view, they are displaying an hour earlier than they should. And in the Day view, they are displaying two (2) hours earlier than they should.

This really does compromise the Calendar's viability, especially for appointment alerts.

The screen shot is at 12:41

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Interestingly, the time zone issues with the calendar events, seems only to effect entries created on the transition date. Entries on the days before are unaffected, and I have just realised by creating today's events, these two are behaving as expected.

This is obviously still an issue, but the scope is narrowed down to the processing of calendar entries on the transition days only. I would expect a similar issue (only reversed) to occur on the day when DST ends.