2nd base?
Vdd,
There is no positive answer towards AO's 2nd base. At the moment, management has never confirmed anything. From what I can see, it all came from crew who are from SYD or MEL and want to return home so badly, they hypothesised all sorts of scenarios then turn their dream into unaccountable rumour. You honestly can't build a career upon such a rumour.
Not to disencourage you, even if there is going to be a southern base in either(or other) city, you can imaging how long the base-transfer waiting list from current crew is going to be.