Extend Your Visa 

Change of Course/Uni 

Are you planning to change your course or the university you are currently associated with? If that's what you intend to do, then there are a few things that you'd need to organize and check before changing your course or institution. 
Firstly, get in touch with the student support service from your respective institution or any relevant advisors. You also need to check the student visa requisites and see if you are following the procedure correctly. 
Note: Always remember to keep a copy of any enrolment paperwork or course cancellation. And, when you change your course or institution, you need to get in touch with the Department of Home Affairs and provide them an eCoE (Electronic Confirmation of Enrolment) from the new institution. 

Changing the course 
If you are planning to change your current course at the same institution that you are in and at the same qualification level, you won't be required to apply for a new student visa (unless the validity of your current visa is about to expire) 
Changing your qualification level 
If you need to change your qualification level, like from a Diploma to a Bachelor's Degree, then you'd be required to apply for a new student visa since your visa Subclass might differ. 
Moving to your new institution 
If you have finally made your mind to move to a different institution, then get in touch with your current one for information associated with this change. In most cases, the new institution will face a restriction before enrolling you if you haven't completed at least six months of the scheduled course under the current visa. 
After you are done with the first six months of your primary course, you will now be able to get yourself permission i.e., to change the institute. You'd be required to have a letter of offer from your new institution to apply for a letter of release from the institution you are about to leave.