I think you need to meet the experience requirements for an Australian PPL (assuming a PPL is what you are wanting to convert to?).
From the CASR part 61
(1) An applicant for a private pilot licence with the aeroplane category rating must have at least 40 hours of aeronautical experience that includes:
(a) at least 35 hours of flight time as a pilot; and
(b) at least 20 hours of flight time as pilot of an aeroplane; and
(c) at least 10 hours of solo flight time in an aeroplane; and
(d) at least 5 hours of solo cross‑country flight time in an aeroplane; and
(e) at least 2 hours of dual instrument time; and
(f) at least one hour of dual instrument flight time in an aeroplane.
so you would need a minimum of 2 hours dual instrument time, at least 1 hour of that must be in an aeroplane. The dual flight IF time for a PPL is normally done in simulated conditions (ie under a hood).