The fare conditions at the bottom actually show the fare code. An 'S' on the end of that fare code generally indicates its a sale fare.
Ok - I called to tripled check the class & I was told that it is eligible for the 2 for 1 flights.
Now for the big question (SYD-ADL)
Either fly economy on Qantas, will have AA membership so have access to the Q lounge
OR
for an extra $150 (total for 2 pax) fly Virgin Business class
I've never flown business class, & unsure whether it's worth it for such a short flight.
Would it be worth it?
I'd go Business for the novelty factor but make sure you fly during a main meal service, not a snack service to ensure you get a proper meal. If you're flying at night and keen to have a few drinks its good fun - CSMs are usually very attentive.