I have problems when I export (publish etc.) calendar data to other systems with recurring items created with auto-date. When I import them in iPad-Calendar or Google-Calendar, only the last item will imported. Looking in the .ics file shows the same UID for all items.

Workaround one was to change the UID, the everything works well. Workaround two was to clean all lines with UID and so the Import to Apple & Google is also OK.

I think, the export implementation of rfc2446 can be a little bit better for recurring items because rfc2446 has in 2.1.5 message sequencing. See RFC 2446 - iCalendar Transport-Independent Interoperability Protocol (iTIP) Scheduling Events, BusyTime, To-dos and Journal Entries

Hagen Frey