see this thread http://www.flyertalk.com/forum/showthread.php?t=834313

i think it's unreasonable to expect CX giving out 4 long-haul redemption tickets in J, booking only four months ahead. even if you booked one year ahead you won't get 4 J tickets. 4 Y tickets, maybe, but not J. CX has to save places for revenue customers.

try redeeming the tickets for short-haul destinations which have lots of flights - Taipei or Singapore, for example. your chances of 4 J tickets on those would be much better. and for long-haul, the more flights there are the better your chances. CX/QF/BA to london may be easier to get in J - there are more flights to LHR than to Jo'burg.

being successful in redeeming flights depends on your ability to plan ahead and be flexible - and it always helps if you're travelling alone. i've been able to redeem at least 2 long-hauls a year in J - and a RTW in J - and i find the asiamiles system to be quite fair.

the alternative is to spend the asiamiles on mobile phones, hotel stays etc. - see the asia miles website.