Q: I was just calling to find out when I can register.
A: You haven't been admitted yet. We haven't received all the required materials for the department to make a decision on your application.
Q: But...school started.
A: Yes it did.
Q: So what am I supposed to do?
A: Well...perhaps you should have considered applying before August 21st. It takes months for some departments to make decisions of applicants. You will need to get all of your required materials in and call the department to see if they can make a rush decision.
*silence*
Q: So does that mean I can't register?

!!!!!!!!!
Did you just wake up last week and decide, "Well I think I'll go to grad school!" You are clearly treating this like ordering something off the value menu at McDonalds! What time schedule are you on? *Sigh*