UA 2071 then DL 5875 at Boston
Chicago O'Hare → Boston → Pittsburgh
Timetable, Boston time
23:35UA 2071 from Chicago O'Hare at the gate
15:00DL 5875 to Pittsburgh leaves the gate
15 h 25 apart on the timetable, overnight
DL 5875 leaves 15 h 25 after UA 2071 arrives on the timetable: more than half a day, so not a connection we count.