Does anyone know how the CTAF frequencies are allocated?
If there is congestion, the process is to raise the issue either via your industry association rep on the W.A. RAPAC or direct to the regional RAPAC Convenor (link below).
The usual process is that the local CASA office will be asked by RAPAC to assess the problem, and make a recommendation. If a discrete frequency is recommended for BUN, Airservices will be asked to allocate one and publish it in ERSA, AIP MAP DAP etc.
You might review past W.A. RAPAC minutes to see if it has been raised before.
https://www.casa.gov.au/about-us/eng...ory-committees