Changes to recurring allday events not sent from iCal - icalendar

Question

I'm running a sabre CalDAV server and I'm using iCal on Yosemite as a client. Now, I create an allday recurring event in iCal and use the Charles Proxy to check the body of the request, that is sent from iCal. Creating the event it sends correct data:
BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Apple Inc.//Mac OS X 10.10.1//EN
CALSCALE:GREGORIAN
BEGIN:VEVENT
CREATED:20160404T203206Z
UID:14C144D6-A872-4D24-91C0-783A9979BB9E
RRULE:FREQ=WEEKLY;INTERVAL=1;COUNT=1
DTEND;VALUE=DATE:20160409
TRANSP:TRANSPARENT
SUMMARY:Repeat
DTSTART;VALUE=DATE:20160404
DTSTAMP:20160404T203206Z
SEQUENCE:0
BEGIN:VALARM
X-WR-ALARMUID:A807798B-DE16-4E62-86E9-C204A2B80F76
UID:A807798B-DE16-4E62-86E9-C204A2B80F76
TRIGGER;VALUE=DATE-TIME:19760401T005545Z
ACTION:NONE
END:VALARM
END:VEVENT
END:VCALENDAR
The response:
HTTP/1.1 201 Created
Date: Mon, 04 Apr 2016 20:32:19 GMT
Server: Apache/2.4.10 (Unix) OpenSSL/1.0.1j PHP/5.6.3 mod_perl/2.0.8-dev Perl/v5.16.3
X-Powered-By: PHP/5.6.3
X-Sabre-Version: 3.0.8
Content-Length: 0
ETag: "55c6a353f278653fdd61387395c274df"
Keep-Alive: timeout=5, max=100
Connection: Keep-Alive
Content-Type: text/html; charset=UTF-8
But if I change a single occurrence of the repeating event and choose to only apply the changes to this occurrence, iCal sends the old calendar-data back to the server without any changes. If I apply the changes to all occurrences, the correct data is sent. If I choose to only apply the changes to future events, it correctly alters the old event and creates a new event for the future occurrences. But then again, no changes on a single occurrence are sent to the server.
This is only happening for allday events. Timed events are working just fine. It also doesn't matter if I create the rrule with "count" or by "until".
If I change a single occurrence and export my calendar from iCal I also get the correct calendar-data, although this data is not sent to the server (different event):
BEGIN:VCALENDAR
METHOD:PUBLISH
VERSION:2.0
X-WR-CALNAME:XXX
X-WR-CALDESC:
X-APPLE-CALENDAR-COLOR:#FF9500
X-WR-TIMEZONE:Europe/Berlin
CALSCALE:GREGORIAN
BEGIN:VEVENT
CREATED:20160405T063102Z
UID:68C23C1E-371C-4799-9139-04F0F8FE6F88
RRULE:FREQ=WEEKLY;INTERVAL=1;COUNT=4
DTEND;VALUE=DATE:20160409
TRANSP:TRANSPARENTSUMMARY:hhhhh
DTSTART;VALUE=DATE:20160404
DTSTAMP:20160405T063102Z
SEQUENCE:0
END:VEVENT
BEGIN:VEVENT
CREATED:20160405T063102Z
UID:68C23C1E-371C-4799-9139-04F0F8FE6F88
DTEND;VALUE=DATE:20160421
TRANSP:TRANSPARENT
SUMMARY:hhhhh
DTSTART;VALUE=DATE:20160418
DTSTAMP:20160405T063102Z
SEQUENCE:0
RECURRENCE-ID;VALUE=DATE:20160418
END:VEVENT
END:VCALENDAR
There, I can finally see the vevent with a correct recurrence-id.
Any ideas? Anyone else ran into a similar problem? I have no idea, what could be causing this...
Thanks in advance!

Answer 1

Okay, this must have been a calendar bug. After enabling debugging I found this error:
Apr 6 12:20:11 XXX.local CalendarAgent[229]: [com.apple.calendar.store.log.ICS] [CaliCalTranslator: Event 97323C3B-753D-46E5-830E-E182BEAA5E0D has invalid instance on date 2016-04-11 00:00:00 +0000. Filtering]
I updated calendar from Version 8.0 (2026) to Version 8.0 (2034.9) and now everything is working as expected.