Welp, that was kind of weird. My account number suddenly disappeared from the login screen and the password and recovery code wasn't working. Fortunately I was able to still log in and when I went to check the home screen apparently my set password and recovery code had vanished. I had to add a new one.
Not sure if that has happened to any of you before. Doesn't seem like someone tried to steal my account and more like the update just erased it somehow. Just in case check if the password and recovery code is still set in case yours hasn't disappeared too.
Edit: Account Number still doesn't show, but at least the recovery code and password are still set. Also everything lost its configuration too, like the option of not having to confirm the use of a skill and battle speed being slow, wtf.