DL 455 then DL 9936 at Atlanta
Washington National → Atlanta → Queretaro
Timetable, Atlanta time
10:56DL 455 from Washington National at the gate
08:00DL 9936 to Queretaro leaves the gate
21 h 04 apart on the timetable, overnight
DL 9936 leaves 21 h 04 after DL 455 arrives on the timetable: more than half a day, so not a connection we count.