Oh god, listen to you all panicking over a few disrupted flights like it spells the end of the airline, talk about drama queens.
The reality is there are spare long haul aircraft sitting around during most of the year to plug the holes when unexpected maintenance crops up. However, the international side of the airline makes nearly all its profit during the Christmas holiday break so they push all the aircraft into service, as you would expect. This means disruptions are harder to handle and you need more creative solutions and you’ll piss off more passengers but that is what running an airline is all about.
Look around, all airlines deal with this stuff. Even Air NZ who bought a new fleet are scrambling to find aircraft to operate their services as the new aircraft can’t fly due to unforeseen maintenance issues. It’s part of running an airline.