SQ 1539 then VA 8287 at San Francisco
Boston → San Francisco → Seattle
Timetable, San Francisco time
00:25SQ 1539 from Boston at the gate
22:35VA 8287 to Seattle leaves the gate
22 h 10 apart on the timetable
VA 8287 leaves 22 h 10 after SQ 1539 arrives on the timetable: more than half a day, so not a connection we count.