Thought it was just the update so spent a good 10 minutes setting up all my classes again. Closed and reopened the game and my classes were gone again.
Jumping in to note that this isn't the case.
Players who logged on prior to 10:05 pm/PT, which was prior to our fix for the issue, would have to remake any classes created during this time. Players who did not log in during this time should be fine.