G'Day Gumaaark
The 'bid' process is still effectively the same. You get a basic list of positions on offer and you choose from them.
As the list can change, you might as well throw in a couple of places you'd like to work at that weren't options, however, we all ended up with placements that were on the original list.
Positions are at individual towers, ie Melbourne is a separate position to Moorabbin.
Before you start training you will find out which stream you're in, you can't really change once you've started (so choose wisely!)
When I applied, AsA were only offering Enroute, but I received a verbal offer for a Tower position which started a couple of months prior to the Enroute position.
I jumped at it and have never looked back.