Outlook导入含RRULE的iCalendar时出现1小时时间偏移问题排查

问题现象 #

• 带有周重复规则（RRULE）的VEVENT事件，设置的本地时间为10:30-12:30，导入Outlook后显示为09:30-11:30（截图粉色区域）
• 删除RRULE行后，事件时间导入Outlook显示正常（截图绿色区域）

涉及时区与完整iCalendar内容 #

使用的Asia/Jerusalem时区定义配置：

BEGIN:VTIMEZONE
TZID:Asia/Jerusalem
LAST-MODIFIED:20230324T084302Z
X-LIC-LOCATION:Asia/Jerusalem
BEGIN:DAYLIGHT
TZNAME:IDT
TZOFFSETFROM:+0200
TZOFFSETTO:+0300
DTSTART:19700327T020000
RRULE:FREQ=YEARLY;BYMONTH=3;BYDAY=-1FR
END:DAYLIGHT
BEGIN:STANDARD
TZNAME:IST
TZOFFSETFROM:+0300
TZOFFSETTO:+0200
DTSTART:19701025T020000
RRULE:FREQ=YEARLY;BYMONTH=10;BYDAY=-1SU
END:STANDARD
END:VTIMEZONE

完整的iCalendar文件内容：

BEGIN:VCALENDAR
PRODID:-//tzurl.org//NONSGML Olson 2023b//EN
VERSION:2.0
BEGIN:VTIMEZONE
TZID:Asia/Jerusalem
LAST-MODIFIED:20230324T084302Z
X-LIC-LOCATION:Asia/Jerusalem
BEGIN:DAYLIGHT
TZNAME:IDT
TZOFFSETFROM:+0200
TZOFFSETTO:+0300
DTSTART:19700327T020000
RRULE:FREQ=YEARLY;BYMONTH=3;BYDAY=-1FR
END:DAYLIGHT
BEGIN:STANDARD
TZNAME:IST
TZOFFSETFROM:+0300
TZOFFSETTO:+0200
DTSTART:19701025T020000
RRULE:FREQ=YEARLY;BYMONTH=10;BYDAY=-1SU
END:STANDARD
END:VTIMEZONE
BEGIN:VEVENT
UID:123
CLASS:PUBLIC
DESCRIPTION:Event1
RRULE:FREQ=WEEKLY;UNTIL=20230707T000000Z
DTSTAMP:20230402T182942Z
DTSTART;TZID=Asia/Jerusalem:20230327T103000
DTEND;TZID=Asia/Jerusalem:20230327T123000
LOCATION:Location1
SUMMARY:Description1
TRANSP:TRANSPARENT
END:VEVENT
END:VCALENDAR

时间显示对比截图 #

内容的提问来源于stack exchange，提问作者Paul