I have an event that is set up using UTC and it recurs over daylight savings time. After the daylight savings time switch, the time is moved an hour. UTC does not use DST, so the time should stay the same. I can add an event after DST with the EXACT same UTC time value and the calendar shows the correct time. I've posted my ICS File below with the recurring event and the one that happens after. Has anyone run into this? Any suggested fixes or changes?
["BEGIN:VCALENDAR\nVERSION:2.0\nPRODID:-//sethhill v1.0//NONSGML //EN\nCALSCALE:GREGORIAN\nMETHOD:PUBLISH\nBEGIN:VEVENT\nDTSTAMP:20120725T222602Z\nDTSTART:20120724T180000Z\nDTEND:20120724T183000Z\nRRULE:FREQ=WEEKLY;UNTIL=20130707T180000Z\nSUMMARY:Class 4 - NODST\nBEGIN:VALARM\nTRIGGER:-PT45M\nACTION:DISPLAY\nDESCRIPTION:NODST\nEND:VALARM\nEND:VEVENT\nBEGIN:VEVENT\nDTSTAMP:20120725T222602Z\nDTSTART:20121120T190000Z\nDTEND:20121120T193000Z\nRRULE:FREQ=WEEKLY;UNTIL=20130707T180000Z\nSUMMARY:Class 4 - TEST1DST\nBEGIN:VALARM\nTRIGGER:-PT45M\nACTION:DISPLAY\nDESCRIPTION:TEST1DST\nEND:VALARM\nEND:VEVENT\nEND:VCALENDAR"]
I was wrong about how DST and UTC work. I was thinking that having a set UTC time meant that the calendar would read it as a set time and display the correct local time auto-magically. In case anyone else is a little confused, think of it like this: MST is UTC-07:00 MDT (DST) is UTC-06:00. If you have a calendar event that is set to repeat throughout the year and it is 18:00 UTC, it will be at 12:00PM MDT or 11:00AM MST. For an ICS file you can either define a STANDARD timezone and a DAYLIGHT timezone, or break the event into multiple parts, with the correct UTC time for each.
I hope this clears things up for someone else.