DL 5598 then DL 1655 at Boston
Cincinnati → Boston → San Francisco
Timetable, Boston time
16:57DL 5598 from Cincinnati at the gate
16:50DL 1655 to San Francisco leaves the gate
23 h 53 apart on the timetable, overnight
DL 1655 leaves 23 h 53 after DL 5598 arrives on the timetable: more than half a day, so not a connection we count.