I have added a CX flight without issue before, also without needing to do a 24 hour stopover. Also had HKG as a previous transit on the itinerary too.
In my case I had booked BNE-HKG-JFK all on CX with an 8 hour transit in HKG, and then later added HEL-HKG-SGN on AY (HEL-HKG) and CX (HKG-SGN) with a 20 hour transit in HKG.
I did have a minor drama at the time of booking when there was only Y available for the CX leg HKG-SGN, but has since been fixed once J seats became available for that particular flight.
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Trying to book Japan domestic flights on JAL is proving to be difficult, with available seats shown on BAEC but the QF call centre operators cannot see any available seats. I am wanting to book flights in September and I am wondering if I am calling too early, assuming this because JAL's own award system doesn't allow for booking domestic flights greater than 2 months away. However when asking the QF call centre to check for award availability 1-2 months away, they still can't see anything, despite award seats showing on both BAEC and JAL.
Has anyone here been able to book Japan domestic flights on JAL as part of a 280k award fare?