Ouch. I can't do more than 8 hours. +1 to hoping you have 1st class or some kind of premium fare.
If any legs of your flight are in the US, good luck. It's a mess here. I fly almost weekly for work, and this week seems scary to me. I flew into DC today and got in right after a bomb threat was called on another flight, a UPS flight crashed in Louisville, and the Dept. of Transportation said they may close US airspace in a few days because the ATC won't receive another check. I am supposed to go home Friday and am crossing my fingers its on a plane and not a rental car.
Hopefully you don't have issues.
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