You apply for GEMSAS and can preference 6 unis. For each uni you can pick to accept CSP/BMP/FFP in whatever order of preference you want. If you select CSP as first preference and BMP as second preference but not FFP then for each uni they will look at your scores and see if you meet the cut offs. If you don't meet it for CSP for pref 1 then they consider BMP for pref 1. If you don't meet that either then they consider CSP for pref 2 etc.
USyd is done outside of GEMSAS (I think you directly apply to USyd) and UQ is outside of the GEMSAS consortium but I think you still apply to UQ through GEMSAS.
So just double checking, if this is my application
1. A: CPS/BMP/FFP
2. B: CPS/BMP
3. C: CPS/BMP/FFP
4. D: CPS/BMP
5. E: CPS/BMP
5. F: CPS/BMP
they first check Uni A's CSP, then Uni A's BMP, then Uni A's FFP, before they check Uni B's CPS to see if I got in right?
In that case, should someone put FFP as first preference? Since this will increase their chance of getting (let's presume that this crazy person doesn't care about the $100k fees because he won the lottery)