VA 8311 then UA 1267 at San Francisco
Boston → San Francisco → Detroit
Timetable, San Francisco time
10:59VA 8311 from Boston at the gate
23:00UA 1267 to Detroit leaves the gate
12 h 01 apart on the timetable
UA 1267 leaves 12 h 01 after VA 8311 arrives on the timetable: more than half a day, so not a connection we count.