Thanks for the feedback everyone.
My original eticket was issued by AA and there is no information on baggage allowance. I still have sliver status with QF so I guess I could get an extra 10 kilos that way if the three bag allowance is not valid. Normally I wouldn't be so worried about this but I've been living in CPT for the last 12 months now relocating to Australia and apart from personal belongings I have a desktop computer to drag along (not fun).