It could be from January, for medical research at least 

“UA anticipates that Australian research funding agencies will, in time, move to a requirement for open access of publicly funded research.” – Universities Australia submission to the Senate committe inquiry on the Data Availability and Transparency Bill (scroll up)

The time could be sooner not later.

The National Health and Medical Research Council is considering requiring research it funds to be open access (either by journals allowing author’s accepted manuscripts to be OA or by researchers depositing new articles in an institutional repository). The proposal is out for consultation but if adopted would apply from January, (CMM April 16).

And Chief Scientist Cathy Foley says she is “closely considering” an OA strategy.

But the Australian Research Council policy remains OA after 12 months, except where “this requirement cannot be met for any reason, including legal or contractual obligations.”