Healthbase Australia has updated the online Australian Medicines Terminology browser to include the 2.27 version of the AMT released by NEHTA recently.
All deprecated versions are still available for browsing/searching.
I can only assume that no-one else in Australia is regularly incorporating the monthly AMT releases into an application. After all this time, the download process still cannot be automated! Perhaps if this were the 1980s NEHTA could publish the updates (with sensible filenames!) via an FTP service. I guess NEHTA still has a lot of catching up to do in order to be implementation ready!