According to the Southwest website twitter log (as of 2 hours ago):
"Sorry, we found an error with the AList Preferred portal that can be fixed by changing your password. ^SW"
I guess the error fairy came to the portal and caused a problem that WE must fix.
I suggest they email every A+ customer and tell us to change our password before we board another wifi flight, which in my case is this Wednesday.
But, how can I be sure the error fairy won't return?