If you miss the timely re-enrolment dates, you can re-enrol late in the Web Enrolment System (WES):
Check miscellaneous fees in early October for the late fee for the 2012 - 2013 re-enrolment period.
The late fee is due with your semester one fees the following academic year.
If your fail to re-enrol, you are no longer considered a student by the University. You have given up your place in the course. You will need to approach your managing faculty to see if you can regain your place.