IT appears that all communications with the Collatz Conjecture project are down.
I have hundreds of completed tasks yet I can't find any reference to reasoning.
Can anyone help?

There is a discussion about this on the Collatz forum:
https://boinc.thesonntags.com/collatz/forum_thread.php?id=95

However, I've just run a task to completion which uploaded a few seconds later so the malady may have been cleared.

I'm still getting timeouts when I attempt to click on your link. My proxy server is showing "No route to host". From my cell phone (Verizon) I get a generic error.

This is a great example of the problem of having a troubleshooting forum on the same infrastructure as the service: there's no way to communicate troubleshooting network infrastructure issues.

I heard from the admin of the Collatz Conjecture project.

"I'm having trouble with the DDNS and had to switch back to the static DNS so it may take a few hours to trickle through. Exit and restart BOINC may also help as it has a tendancy to cache the DNS entries. "


So there's the answer.