Hello Michael,
Sorry to hear your deliveries are slow.
All our overseas issues are sent out from the UK by Air, essentially at the same time. Many overseas newsagent copies go by surface mail.
Subs copies should only take a few days to get to the country of destination, we are then at the mercy of the local postal services.
We are aware of a handful of countries where there are local delays and Australia seems to be one of these, but subs copies should still be faster than newsagent ones.
Neil