There is no requirement for the minister to process applications in any particular timeframe, or at all; notwithstanding section 65
MIGRATION ACT 1958 - SECT 65
Decision to grant or refuse to grant visa
(1) Subject to sections 84 and 86, after considering a valid application for a visa, the Minister:
(a) if satisfied that:
(i) the health criteria for it (if any) have been satisfied; and
(ii) the other criteria for it prescribed by this Act or the regulations have been satisfied; and
(iii) the grant of the visa is not prevented by section 40 (circumstances when granted), 91W (evidence of identity and bogus documents), 91WA (bogus documents and destroying identity documents), 91WB (applications for protection visas by members of same family unit), 500A (refusal or cancellation of temporary safe haven visas), 501 (special power to refuse or cancel) or any other provision of this Act or of any other law of the Commonwealth; and
(iv) any amount of visa application charge payable in relation to the application has been paid;
is to grant the visa; or
(b) if not so satisfied, is to refuse to grant the visa.
and now see Section 39:
MIGRATION ACT 1958 - SECT 39
Criterion limiting number of visas
(1) In spite of section 14 of the Legislation Act 2003 , a prescribed criterion for visas of a class, other than protection visas, may be the criterion that the grant of the visa would not cause the number of visas of that class granted in a particular financial year to exceed whatever number is fixed by the Minister, by legislative instrument, as the maximum number of such visas that may be granted in that year (however the criterion is expressed).
(2) For the purposes of this Act, when a criterion allowed by subsection (1) prevents the grant in a financial year of any more visas of a particular class, any outstanding applications for the grant in that year of visas of that class are taken not to have been made.
Because of the money various parties can can rake in, students are most unlikely to be told they have not made an application, but 'cap and cease is available' .
For fun, search: cap and cease.
The good ship Titancic steams on.