It should take around 6 months (the time between an AIP MAP data cut-off date and the release's effective date). Example: the cut-off date for AIP MAP effective at the end of this year would be early June.
WACs aren't published as frequently though, but publication in AIP MAP is sufficient.
My last experience was it was simply a matter of providing details of the ALA (lat/long., owner & contact details, charts affected) to the Airservices Aeronautical Information Management people. They had a standard form to complete.
Who are you going through (don't say CASA....)?
See the links under "Changes to aeronautical charts and documents" here:
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