DL 1091 then AF 2519 at San Francisco
Salt Lake City → San Francisco → Seattle
Timetable, San Francisco time
23:59DL 1091 from Salt Lake City at the gatealso VS 4542
10:31AF 2519 to Seattle leaves the gate
10 h 32 apart on the timetable, overnight
The last days
DL 1091 and AF 2519 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.