But the problem here is - will AUH security confiscate these purchases during your transfer? I know that some other airports do this. You can always ask at duty-free - they will know which airports allow this, and which don't. The person selling you liquids at duty free should ALWAYS ask where your final destination is, and where any intermediate stop(s) will be.
There is one foolproof and safe way to make sure you can keep your duty-free purchases. Buy them at the airport of departure of your
final flight. So, buy in AUH, rather than in the UK.
However, on arrival in Australia (definitely in Sydney (
http://www.syddutyfree.com/default.aspx) and Melbourne (
http://www.firstdutyfree.com.au) but probably in the other international gateways too), you can buy your full Australian duty-free allowance
on arrival, immediately before immigration and customs. You can even buy online (on the websites listed above), and they will have it ready and waiting for you to collect as you walk from the plane to immigration.