DL 400 then DL 5679 at Boston
San Francisco → Boston → Louisville
Timetable, Boston time
15:45DL 400 from San Francisco at the gate
09:55DL 5679 to Louisville leaves the gate
18 h 10 apart on the timetable, overnight
DL 5679 leaves 18 h 10 after DL 400 arrives on the timetable: more than half a day, so not a connection we count.