Unfortunately we don't really have much protection in Australia when it comes to error fares. My understanding is that normal contract law applies, and if the airline can satisfy the elements of mistake, you'll be out of luck.
Of course the airline can always cancel first, and then you'll have the battle to get it reinstated.
Travel insurance is unlikely to cover any expenses in this case. Nor is the airline.
There are perhaps some exceptions - if you call the airline and they explicitly tell you (or even better, write to you) that they will honour the fare, you are somewhat protected (not that they won't ultimately cancel, but at least your incidental costs would have to be covered by them).
Time is another factor that can sometimes work in your favour. If several months pass the airline may have a hard time denying you any incidental expenses you incur.
However - I think the advice given is sound - do not book any non-refundable connecting flights or hotels until you have some idea whether the fare will be honoured.