Hi All.
Grateful for any advice.
Have tried for 3 nights at midnight to book a J reward flight with Avios but after getting all the way through the process I keep getting "Sorry we have been unable to complete your transaction ... phone the office" My guess is that an agent nabs the seats before my booking can create a reservation in the system.

Previously I've called BA Australia to book a flight but that number is now out of service. The UK number is useless because it doesn't open until 6am.

Does anyone know a working Avios flight booking number that is open at midnight GMT?