Hi Thrustmax,
I am in a similar position to you with a CPL that i have not used for some years since moving to the UK. Did you ever go through the process to convert to a UK license? My understanding from the local flying club was i need to go back to Australia and complete a flight review. With an updated logbook stamped with a Biennial flight review i would then be able to go through the conversion to a UK license. Does that sound familiar?