See itin here:
View attachment 273946
I could confirm the itinerary on Qantas website - tickets not issued yet. Got that generic error so I called up QF at around 2am, got transferred to NZ centre and kind lady helped me to book. By that time however, QR showed no U inventory on any flight in or out of Doha. Other segments were fine.
The curious thing is that I had checked on BA to confirm availability for direct LHR-DOH and DOH-HKG flights (which there were) literally two or three hours ago before I got on the phone, and I even had contingencies like LHR-MUC-DOH and DOH-SIN-HKG; however these now all show X only, also on BA. So it's borderline impossible for someone to snap everything up, unless the even the BA system is showing phantoms.
Expertflyer also doesn't show QR availability, "our provider is having problems"...
Unless a hundred people snagged seats for even things like LHR-CPH-DOH, LHR-MUC-DOH etc, I don't think that's the case. I confirmed all the available sectors and dates on BA as well before booking, but at 2am AU time the U invent was all gone. Even today:
View attachment 273947
Only RJ has J availability in and out of DOH..