UNTIL not handled correctly if it falls into a DST change

[minichma]

Describe the bug
UNTIL not handled correctly if it falls into a DST change.

The following VEVENT should produce two occurrences, but it produces only one:

DTSTART;TZID=Europe/Amsterdam:20201024T023000
DURATION:PT5M
RRULE:FREQ=DAILY;UNTIL=20201025T010000Z

The expected occurrences are at 20201024T023000 and 20201025T023000 but the latter is not returned. I.e. 20201025T023000 exists twice in CET due to a DST change at 3:00 back to 2:00.

Environment (please complete the following information):

• .NET version: .net 8.0
• ical.net version: 5.0.0-pre.41

[axunonb]

Nice! Was this the result a systematic approach or was it more of a coincidence?

[minichma]

Actually, while trying to migrate our project to v5, I'm trying to remove many of the workarounds that were required with v4, but now some tests start failing. That's how I identify these edge cases.