DL 2639 then DL 5875 at Boston
New York JFK → Boston → Pittsburgh
Timetable, Boston time
22:55DL 2639 from New York JFK at the gate
15:00DL 5875 to Pittsburgh leaves the gate
16 h 05 apart on the timetable, overnight
DL 5875 leaves 16 h 05 after DL 2639 arrives on the timetable: more than half a day, so not a connection we count.