F9 3453 then DL 9970 at Atlanta
New York LaGuardia → Atlanta → Los Angeles
Timetable, Atlanta time
20:27F9 3453 from New York LaGuardia at the gate
17:01DL 9970 to Los Angeles leaves the gate
20 h 34 apart on the timetable, overnight
DL 9970 leaves 20 h 34 after F9 3453 arrives on the timetable: more than half a day, so not a connection we count.