UA 4258 then KL 652 at Dulles
Cincinnati Northern Kentucky → Washington → Amsterdam
Timetable, Washington time
21:22UA 4258 from Cincinnati Northern Kentucky at the gate
18:15KL 652 to Amsterdam leaves the gate
20 h 53 apart on the timetable, overnight
KL 652 leaves 20 h 53 after UA 4258 arrives on the timetable: more than half a day, so not a connection we count.