DL 343 then DL 2597 at Atlanta
Washington National → Atlanta → Montréal
Timetable, Atlanta time
09:55DL 343 from Washington National at the gate
09:00DL 2597 to Montréal leaves the gate
23 h 05 apart on the timetable, overnight
DL 2597 leaves 23 h 05 after DL 343 arrives on the timetable: more than half a day, so not a connection we count.