UA 503 then DL 5622 at Boston
Newark → Boston → Richmond
Timetable, Boston time
09:17UA 503 from Newark at the gate
08:50DL 5622 to Richmond leaves the gate
23 h 33 apart on the timetable, overnight
DL 5622 leaves 23 h 33 after UA 503 arrives on the timetable: more than half a day, so not a connection we count.