Fwiw - I haven't stepped foot in a learning institution in well over 10 years. If you're dedicated to doing it then its not always necessary to be face to face.

Have a look at the subjects and talk to the course coordinator as you may be able to start the cert IV and transfer over to the diploma later and possibly have credits for the units already completed. I know I chopped my business admin (medical) in half as I'd already done a similar course.