DL 2818 then UA 571 at Atlanta
Roanoke → Atlanta → San Francisco
Timetable, Atlanta time
07:33DL 2818 from Roanoke at the gate
07:00UA 571 to San Francisco leaves the gate
23 h 27 apart on the timetable, overnight
UA 571 leaves 23 h 27 after DL 2818 arrives on the timetable: more than half a day, so not a connection we count.