I have a situation where users are making appointments now, but their appointment time is set in a few weeks (when daylight saving time starts in my area). The ics file that is generated in the code seems to show the correct time, which is 8:35am in about 2 weeks time when daylight time switches over.
BEGIN:VTIMEZONE
TZID:Australia/Sydney
LAST-MODIFIED:20201011T015911Z
TZURL:http://tzurl.org/zoneinfo-outlook/Australia/Sydney
X-LIC-LOCATION:Australia/Sydney
BEGIN:STANDARD
TZNAME:AEST
TZOFFSETFROM:+1100
TZOFFSETTO:+1000
DTSTART:19700405T030000
RRULE:FREQ=YEARLY;BYMONTH=4;BYDAY=1SU
END:STANDARD
BEGIN:DAYLIGHT
TZNAME:AEDT
TZOFFSETFROM:+1000
TZOFFSETTO:+1100
DTSTART:19701004T020000
RRULE:FREQ=YEARLY;BYMONTH=10;BYDAY=1SU
END:DAYLIGHT
END:VTIMEZONE
BEGIN:VCALENDAR
VERSION:2.0
CALSCALE:GREGORIAN
BEGIN:VEVENT
DTSTART;TZID=Australia/Sydney:20231010T083500
DTEND;TZID=Australia/Sydney:20231010T085500
DTSTAMP:20230924T014000
DESCRIPTION:Reminder for 10/10/2023 8:35 AM
LOCATION:NSW
UID:[email protected]
SUMMARY:test summary
BEGIN:VALARM
TRIGGER:-PT15M
ACTION:DISPLAY
END:VALARM
END:VEVENT
END:VCALENDAR
In the calendar program on mac it shows the correct time of 8:35am. However on Outlook and the calendar in windows it shows as 9:35am. I have fiddled around with changing the TZ Offset but it always seems to show as one hour off. I have also looked at other questions on here and none of them seem to have this problem with outlook specifically, in this specific scenario of setting an appointment at a future time in which the timezone changes.
Is there a way I can make it so the correct time is shown on all calendar programs, without messing one of them up? Or is it simply a windows setting that needs to be changed? If it is, then I suppose I could direct my users to change their settings on windows but this is not ideal as I cannot communicate with a new user that I don't know about yet.