BEGIN:VCALENDAR
VERSION:2.0
PRODID:icalendar-ruby
CALSCALE:GREGORIAN
METHOD:PUBLISH
BEGIN:VTIMEZONE
TZID:Europe/London
BEGIN:DAYLIGHT
DTSTART:20270328T020000
TZOFFSETFROM:+0000
TZOFFSETTO:+0100
RRULE:FREQ=YEARLY;BYDAY=-1SU;BYMONTH=3
TZNAME:BST
END:DAYLIGHT
BEGIN:STANDARD
DTSTART:20271031T010000
TZOFFSETFROM:+0100
TZOFFSETTO:+0000
RRULE:FREQ=YEARLY;BYDAY=-1SU;BYMONTH=10
TZNAME:GMT
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BEGIN:VEVENT
DTSTAMP:20261112T131602Z
UID:eyeball-grad-ball-2027
DTSTART;TZID=Europe/London:20270511T183000
DTEND;TZID=Europe/London:20270512T020000
LOCATION:Oran Mor 
SUMMARY:Eyeball / Grad ball 2027
END:VEVENT
END:VCALENDAR