I fly out of Dulles (IAD) and am not looking forward to this.
A bunch of 380’s arrive at the same time (or nearly so) and the zoo that is passport control becomes a huge, nasty, hours long nightmare because you can bet the CBP is not planning anymore hires to help process all those extra passengers. Also, the scheduling mess that follows is something no one has considered; i.e., connections from arriving international flights can be close, and now with the impending clog in passport control, this means a lot more missed connections and/or slipping of connection flights, meaning lost time and increased cost.
Yuck.
In a typical three class international configuration, an A380 carries 525 passengers, while a 747-400 carries 416 passengers.
The arrival of a bunch of either aircraft at the same time is likely to cause long lines.
Hopefully, they’ll be able to work that out and hire more people with that many more passengers passing through the system.