Then why isn’t it fixed? I reported it!
Guess it will be If nobody else is doing it, maybe I can, but not at the moment.
I don’t think you should challenge the stability of software in real-world usage.
For this reason, DAVdroid actually generates iCals with “@” in the UID, but a file name where the “@” is replaced by “_”. Maybe this approach would be useful for Contacts and Tasks, too.
However, there are other servers (Zimbra as far as I remember) which don’t accept file names that are not the same as the UID and will redirect accordingly.
Maybe new UIDs should be really generated without @ too, or at least Contacts and Tasks should have file names where the “@” is replaced by “_” too.
On the other side, people will still report strange problems from time to time nevertheless until the problem is fixed upstream.