Buying business class in S'pore for SIN-SYD-SIN will cost >S$4700 + tax but if you buy an 1-year economy for S$800 and then buy the business class from Sydney for SYD-SIN-SYD, it will only set you back A$3000.

Have done this numerous times to fit budget constraints but it works.

Anyone done this ?

Also, SIA now has a 14-day max. SIN stopover for business class if you are going beyond S'pore. They must have noticed mine and other FF buying habits, eg. SYD-SIN-LHR return. I used to save S$5000 doing this when there was no limitation and I could stay in Singapore as long as I want to a max. of 1 year.