Y4 2734 then TP 4392 at San Francisco
Las Vegas → San Francisco → Boston
Timetable, San Francisco time
17:09Y4 2734 from Las Vegas at the gatealso F9 4157
10:44TP 4392 to Boston leaves the gate
17 h 35 apart on the timetable, overnight
TP 4392 leaves 17 h 35 after Y4 2734 arrives on the timetable: more than half a day, so not a connection we count.