Looks very like, although the server is 'there' and responding to the login server, Europa has lost it's connection to the character data so you can't get to select a character to play...
In the past, when I was running networks, it was a fairly common error for people to test a server was 'up' by simply prompting it to respond, but what you really need to do is not simply see it is physically present but also make sure it is functioning as it is meant to. I'm suspecting the automated systems monitoring the UO servers are only doing the most basic 'is it there' check, so never triggered anything to tell the devs there was a problem.... until, with luck, they see the feedback from players and start looking at it.