ATC could well have handled the malcontent CX flight the way Tehran handled Speedbird one night a few years ago...when complaining about the lower level and needing possibly to refuel, Tehran ATC issued the THR weather and the contract fuel price, issued descent clearance (when ready) and further stated...y'alls welcome, we can offer a quick turn...Speedbird clammed up.
Gotta put 'em in their place.
The Brits and the Aussies are 'complainers'...in
the extreme.
Having said this, the CX boys and girls are trying to squeeze more dough out of Swire and Company (they'll be lucky)...and are quite militant at the present time.
Actually, I wish the CX guys (and gals) good fortune, as CX is making millions (billions) presently.
IE: pay up or...else.