AC 3997 then QF 3741 at San Francisco
Boise → San Francisco → San Diego
Timetable, San Francisco time
09:23AC 3997 from Boise at the gatealso UA 4639
11:53QF 3741 to San Diego leaves the gate
2 h 30 apart on the timetable
The last days
AC 3997 and QF 3741 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.