The issue to hit these servers is the same as the one to hit our P1 server this morning:
Thankfully we already know what the fix is and are applying it to the affected servers. The fix is applied account-by-account and it takes a couple of seconds per account.
If you are experiencing this issue now - it will be resolved in the very near future as we are already in the process of applying it.
While it is applying - we are investigating ways to speed up the process.