DavDroid doesn’t handle exceptions from weekly recurring appointment correct. The exceptions don’t appear on the mobile phone, but they appear in owncloud, which I use as caldav server. I can provide you with an example ics file, if needed.
@rfc2822 Thanks for you attention to this issue. I got it to work. Uninstalled both apps, rebooted phone, reinstalled both apps and now it is working. Must have been some hiccup that needed a reboot to clear out.