F9 1596 then DL 2597 at Atlanta
Chicago O'Hare → Atlanta → Montréal
Timetable, Atlanta time
13:32F9 1596 from Chicago O'Hare at the gate
09:00DL 2597 to Montréal leaves the gate
19 h 28 apart on the timetable, overnight
DL 2597 leaves 19 h 28 after F9 1596 arrives on the timetable: more than half a day, so not a connection we count.