F9 1263 then DL 903 at Atlanta
Detroit → Atlanta → Seattle
Timetable, Atlanta time
09:04F9 1263 from Detroit at the gate
21:20DL 903 to Seattle leaves the gate
12 h 16 apart on the timetable
DL 903 leaves 12 h 16 after F9 1263 arrives on the timetable: more than half a day, so not a connection we count.