I have applied for APS 4 months ago but still did not receive my certificate. And without APS I cannot proceed with further steps like accomodation, Health Insurance, VISA . etc. They are not even responding us. So, this is creating tension and anxity.
One advice I can give you, e-mail your university regarding this and ask them to mail for speeding up the process and stating that you are going to enroll in that university in next semester.