If you are cash rich you should be holding a reserve of back-up aircraft. Certainly for jets a 707 flies to the same schedule as a 747 and you can reduce your fuel bill, save your slots, even sack a few crew, what ever it take to get thro the event. Piston engines were fine with the volcanic ash, it was the hot core of the jets that got coated with liquid glass, and when it cooled it became very abrasive on the next start up.
Disasters happen. Responding is a core of any modern business strategy when it comes to borrowing from the banks. They really don't like you taking risks with their money.
The odd ball is that your aircraft insurance becomes unnecessary as your fleet size and capital allows you to survive replacing a few aircraft if the are lost/crashed.
The routine change of the country's government, and attitude to noise / pollution control as a vote winner, is something Sami hasn't written in YET.
The shenanigans that are going on around the next London Airport are an example. Knock down a few thousand homes to expend Heathrow, build a new Island in the Thames estuary, or expand Gatwick and blight the homes of the rich (and well connected) retire-ees. Should have gone to the old American airbase north of oxford but that's been sold to a housing developer. M5 and rail links within two miles and a 3 hour commute catchment area that covers all the big cities in the country. Feel better now, rant over.