Presuming that you are flying AA on SAN-LAX, you can just stay inside security in T4 and get the QF BP in the lounge in T4. QF reprints it in order to process the ETA (if applicable), so it really isn't optional. AA in SAN cannot do this, thanks to the incompatibilities in the Oneworld computer systems. Of course LAX-AKL departs from TBIT, so you will have to go landside and re-clear security, no matter what you do for BPs.