AM 978 then DL 9936 at Atlanta
Monterrey → Atlanta → Queretaro
Timetable, Atlanta time
10:55AM 978 from Monterrey at the gate
08:00DL 9936 to Queretaro leaves the gate
21 h 05 apart on the timetable, overnight
DL 9936 leaves 21 h 05 after AM 978 arrives on the timetable: more than half a day, so not a connection we count.