This has been possible since both BBSW and the cash rate are supported by underlying markets with enough transactions to calculate robust benchmarks. We have been encouraging users of Australian dollar benchmarks to be choosing the benchmark that is most appropriate for their circumstances. Sometimes it makes sense to use a credit-based benchmark, such as BBSW, particularly when banks are issuing funding instruments.
However, it often makes more sense to use a risk-free benchmark, such as when governments raise funding. There has been progress on this in recent months, with the South Australian Government Financing Authority issuing the first FRN referencing the cash rate. Nevertheless, the lesson from LIBOR is that no benchmarks should be taken for granted.