We are flying United from STT to Dulles/Washington, DC on a Sunday.  Flight departure from STT is 12:40 PM.  How early are you supposed to arrive at the airport before departure time?  Not sure if this counts as domestic (1-1.5 hrs prior) or international (2+ hrs prior). Don't particularly want to sit at the STT airport for several hours awaiting our flight departure, but it looks like ferry service from Cruz Bay to Crown Bay is limited on Sundays.