UA 1389 then TP 4392 at San Francisco
Denver → San Francisco → Boston
Timetable, San Francisco time
21:10UA 1389 from Denver at the gatealso AC 5331, OZ 6351, VA 8352, NZ 9069
10:44TP 4392 to Boston leaves the gate
13 h 34 apart on the timetable, overnight
TP 4392 leaves 13 h 34 after UA 1389 arrives on the timetable: more than half a day, so not a connection we count.