Getting "Invalid date 'APRIL 31'" when specification of time for EXDATE is missing

[rfc2822]

Discussed in #146

^{Originally posted by bwildenhain March 27, 2024}
Hi,

when trying to sync a Nextcloud calender, which contains the recurring event from
btest.ics.txt
I get the following error message: Invalid date 'APRIL 31'

Although https://icalendar.org/validator.html, GNOME Evolution and Nextcloud Calendar didn't complain and excluded the 31st of may (sic!), the file using only a date where date + time where required for the EXDATE line, so
EXDATE;VALUE=DATE:20240531
seems to be wrong wrong, while
EXDATE;TZID=Europe/Berlin:20240531T114500
was working. The following debug output was created:

debug-info.txt

I wonder whether it might be a good idea to output a more understandable error message or to handle this more gracefully by accepting the file nevertheless and interpreting it accordingly. I have no experience in kotlin programming, so I didn't look into the actual source code.