Yes he contacted BA and they could only switch him to a flight that had Reward availability whereas Qatar were happy to switch me to any other flight.

incidentally if you try to transfer more avios than you personally have from BA to QR they just allow you to do so and subtract the extra from your household account, in the same manner that they would take them on a BA redemption if you didn’t personally have enough Avios but your household did.

Worked for me.