DL 639 then B6 9003 at Boston
Los Angeles → Boston → Columbia
Timetable, Boston time
14:56DL 639 from Los Angeles at the gate
09:50B6 9003 to Columbia leaves the gate
18 h 54 apart on the timetable, overnight
B6 9003 leaves 18 h 54 after DL 639 arrives on the timetable: more than half a day, so not a connection we count.