Gah. First agent told me there'd be no problem getting award flights LHR-HKG/NRT-ICN.
Phoned back to check dates and the agent says it's not possible to mix BA and non-BA carriers in this way? So the HKG-ICN (CX) or NRT-ICN (JAL) wouldn't be allowed. "But we can get you there all the way on JAL sir - in J only".
Am I barking up the wrong tree here?
(Can't find any reference on BA.com for this kind of situation - only for flying two or more partner airlines in addition to BA.)