Aircraft maintenance cycles are based upon hours flown, as opposed to mileage. Quantas and Singapore Airlines, due to their countries of origin, operate about the longest flight routes in the industry. Therefore, while a Quantas plane may have the same number of flight hours as say, one from Emirates, the Quantas plane probably has a significantly LESSER number of evolutions ( a take off and a landing ) As these are generally the causes of greatest stress on the airframe, it stands to reason that other 380s have an even greater probability of metal fatigue/stress.
If you remember the Hawaiin Airlines palne years ago that lost the top of the passenger cabin in mid air..it peeled back like a can of sardines...it was later determined that because the airline operated mainly short hops between the islands, the plane in question had THREE time the number of flight evolutions as the average similar airframe with the same number of flight hours.
I remember that Hawaiian flight. IIRC, it had over 80,000 takeoffs and landings under it.
Was that the Aloha Airlines flight?
A link to Wikipedia:
It doesn't sound like the pressurization/depressurization cycle is an issue here, since wings don't get pressurized. We don't know if the cracked parts compromise the structural integrity of the A/C or what caused the cracking in the first place (Fatigue caused by flex due to wing loading/unloading? Vibration of the Engines? Unforeseen Aerodynamic forces, like clear air turbulence?)
My point is that the number of landing cycles may not apply here.