Hi,
after some relatively recent update, when trying to create a contact in the stock Contacts app, a new dialog appeared asking where to save contacts. The only option available was "Only this device" (my translation, not sure about the original English label). I've selected this option and then the regular contact adding dialog was available, and there I could select my remote DAV address book.
IMHO the new dialog is confusing users who have remote address books configured. I don't know where it comes from and if it can be improved or removed.
Greets.