Wonderfully helpful, hauteboy. Many thanks for all your hard work.

One tiny thing: using a Mac and Safari, Apple's browser bundled with OSX, it's not possibe to choose any tier point calculator other than Qantas, e.g. clicking on the BA radio button results in BOTH the Qantas and BA buttons being chosen simultaneously (something which should be impossible) and QF tier pts still being shown.

Otherwise it works perfectly.