DL 8839 then DL 5679 at Boston
Memphis → Boston → Louisville
Timetable, Boston time
13:30DL 8839 from Memphis at the gate
09:55DL 5679 to Louisville leaves the gate
20 h 25 apart on the timetable, overnight
DL 5679 leaves 20 h 25 after DL 8839 arrives on the timetable: more than half a day, so not a connection we count.