BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//apizt//Original teaching reference//EN
CALSCALE:GREGORIAN
BEGIN:VTIMEZONE
TZID:America/New_York
BEGIN:DAYLIGHT
DTSTART:20070311T020000
RRULE:FREQ=YEARLY;BYMONTH=3;BYDAY=2SU
TZOFFSETFROM:-0500
TZOFFSETTO:-0400
TZNAME:EDT
END:DAYLIGHT
BEGIN:STANDARD
DTSTART:20071104T020000
RRULE:FREQ=YEARLY;BYMONTH=11;BYDAY=1SU
TZOFFSETFROM:-0400
TZOFFSETTO:-0500
TZNAME:EST
END:STANDARD
END:VTIMEZONE
BEGIN:VEVENT
UID:class-20261020@apizt.invalid
DTSTAMP:20261017T000000Z
DTSTART;TZID=America/New_York:20261020T180000
DTEND;TZID=America/New_York:20261020T190000
RRULE:FREQ=WEEKLY;COUNT=6
EXDATE;TZID=America/New_York:20261103T180000
SUMMARY:Light observation class
END:VEVENT
BEGIN:VEVENT
UID:class-20261020@apizt.invalid
DTSTAMP:20261017T000000Z
RECURRENCE-ID;TZID=America/New_York:20261110T180000
DTSTART;TZID=America/New_York:20261112T180000
DTEND;TZID=America/New_York:20261112T190000
SUMMARY:Light observation class rescheduled
END:VEVENT
END:VCALENDAR