Oh it doesn't remember that. When u leave the server it sets u back to civilian and when u join it sets you to civilian. You can change it using !class when you're playing, but there's a time limiter on it so you can't use it every 2 seconds. What it remembers is your money, ur bank account, and hopefully in the future it will remember items you bought like a car for example. When u join u can spawn ur car, then when u leave it gets deleted.