LA 6139 then CM 1472 at San Francisco
Boston → San Francisco → Seattle
Timetable, San Francisco time
23:58LA 6139 from Boston at the gate
22:35CM 1472 to Seattle leaves the gatealso UA 5579, NZ 9401
22 h 37 apart on the timetable, overnight
CM 1472 leaves 22 h 37 after LA 6139 arrives on the timetable: more than half a day, so not a connection we count.