Thanks to Garry and he’s fuck up some of the players were unable to join the server because of the Steam Auth Timeout error.
This have been updated so anyone that had the issue will now be able to join.

We like to apologize on behalf of Garry for the error in judgment today.

Garry’s Twitter Feed

“Sorry guys, I'm tired, I released a client update instead of a server update. Update is out for real now. Servers will need to be restarted.”