DL 9951 then DL 823 at Atlanta
Queretaro → Atlanta → San Francisco
Timetable, Atlanta time
20:38DL 9951 from Queretaro at the gate
14:49DL 823 to San Francisco leaves the gate
18 h 11 apart on the timetable, overnight
DL 823 leaves 18 h 11 after DL 9951 arrives on the timetable: more than half a day, so not a connection we count.