UA 3870 then DL 2477 at San Francisco
Xiamen → San Francisco → Salt Lake City
Timetable, San Francisco time
07:49UA 3870 from Xiamen at the gate
19:21DL 2477 to Salt Lake City leaves the gatealso VS 4457, WS 5408
11 h 32 apart on the timetable
The last days
UA 3870 and DL 2477 weren’t both flown 15 min to 12 h apart in the last 21 days.
Statistics from past flights, not live flight information. Always check times and your connection with your airline, and don’t base travel or booking decisions on these numbers.