SQ 1539 then DL 4679 at San Francisco
Boston → San Francisco → Atlanta
Timetable, San Francisco time
09:40SQ 1539 from Boston at the gate
08:24DL 4679 to Atlanta leaves the gate
22 h 44 apart on the timetable, overnight
DL 4679 leaves 22 h 44 after SQ 1539 arrives on the timetable: more than half a day, so not a connection we count.