Flight deck duty time is not used in Australia
Sorry NN, not correct. My company operates under the CAO General exemption and Flight Deck Duty (FDD) is certainly there, and used. Currently on non-augmented flights we don't approach the FDD limits. On augmented flights with up to 16+ hour duty limits each pilot has around a 10 hour (plus/minus a bit depending on sign on times, number of sectors etc.) flight deck limit.
We don't log the times as such but split the cockpit time amongst the crew to ensure that the FDD is not broken. Have heard though that there are possibly Oz airlines that do keep a log and I guess that is what WITWIW is asking.