UA 4521 then AA 5220 at Dulles
Greenville-Spartanburg → Washington → Charlotte
Timetable, Washington time
11:55UA 4521 from Greenville-Spartanburg at the gate
11:48AA 5220 to Charlotte leaves the gate
23 h 53 apart on the timetable, overnight
AA 5220 leaves 23 h 53 after UA 4521 arrives on the timetable: more than half a day, so not a connection we count.