I think I am now getting a similar issue when attempting to log on, but some slightly different results.
Firstly, when I attempt to log on I am greeted with the login prompt. I've never been greeted with this screen before this problem started.
I enter my correct credentials, and the game window opens up. However, instead of taking me to the beta disclaimer screen, I get fatal error 30 and fatal error 31, and my game crashes.
I have not yet attempted a reinstallation, and I have not changed any steam settings. I have not been able to connect since the day of the world wrapping update.