I believe you can create a free AsiaMiles account, but I’ve never seen seat availability through it, though maybe I haven’t been looking in the right places. Though that would show CX flights. I’m not sure about JAL.
I’m sure someone with extensive knowledge will be on in the (later) morning with some better answers, sorry I can’t be of more help.
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Try Expedia AU site and specify JAL as the carrier. Seat availability will show up for the chosen flight. If there's good availability there may also be some award seats.
From my knowledge, Qantas does not use normal CX award fare bucket for QFF points booking.
I have seen CX sectors showing up on qantas award booking website early this year but it does not seem to appear anymore. (Could any confirm that?)
As for Asiamiles redemption availability, there is a page within Asiamiles' website that will indicate award availability. It is not very informative but it does help. http://www.asiamiles.com/am/en/redeem/flights/seats
PS: CX's control hides / releases award seats for elite FF but not sure if that extends into QFF (Because you can't book with CX directly)
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