personally I’ve heard from others I wouldn’t recommend iflyflat. it’s very expensive and service is indifferent, he charges $2500 per return booking. so you would pay $10,000 for your family of 4. which is more than one return business ticket to Europe. Which is for at most a few hours of searching or sometimes less.
you can easily book flights to London yourself . the Qantas Frequent flyer rewards flight search is very easy to follow, just be flexible on dates. the only caveat is you are unlikely to get 4 seats together . another alternative as Jimmy said is call Qantas directly. as a platinum you get premium service so they will find flights for you, it’s actually $70 per person (from 1 May) or 6,000 points which you could easily use (not sure if this goes up). for for a small fee of 24,000 points or $280 (+ taxes) vs $10,000, you choose.
best to have flexible dates in mind.
you have 2 airline options to get to London using QFF points via Dubai
- Qantas via Dubai
- Emirates via Dubai (although some bookings are via Bangkok then Dubai)
however using these other airlines may give you more options on available seats. Qatar would have similar journey time
- British Airways via Singapore
- Cathay via Hong Kong
- Malaysia via Kuala Lumpur
- Japan Airlines via Tokyo
- Qatar via Doha
Although some flight options particularly via HK and Singapore or even Bangkok may mix up airlines.
if you want longer than a 24 hour stopover it will be treated as 2 leg bookings and cost more points.
hope this helps