Unsure if you (the OP) means booking code F or a ticket in First Class. If the later and if a part of an AONEx fare, then expect nothing from the invol downgrade. Been there, complained, and nothing eventuated - but it was on a CX issued ticket, so AA may be a different outcome.
Not part of AONEx. The fare for JNB-SYD is FOW and not sure why it was booked to A class.
Called QF yesterday that just referred me to AA. Called AA that told me that QF should reaccomondate me. Called back QF and got this unbelievably cocky lady in Melbourne. I certainly wouldn't have minded this downgrade ex-Europe when QF would have been liable to refund 75% of the total ticket price.
We'll see what the airport will do for me on Tuesday. I had couple of involv downgrades when I was ticketed in EK F (paid) earlier this year and they handle these rather professionally. They throw miles at your + free RT ticket in the original booking class for the segment that you were downgraded and you can extend it as well. I do understand that there are equipment swaps etc but the airline should then make sure that passengers are not inconvenienced.