AA 1509 then DL 2597 at Atlanta
Cleveland → Atlanta → Montréal
Timetable, Atlanta time
09:08AA 1509 from Cleveland at the gate
09:00DL 2597 to Montréal leaves the gate
23 h 52 apart on the timetable, overnight
DL 2597 leaves 23 h 52 after AA 1509 arrives on the timetable: more than half a day, so not a connection we count.