UA 5955 then AA 3176 at LAX
Seattle (SEA) → Los Angeles → San Francisco
Timetable, Los Angeles time
21:28UA 5955 from Seattle (SEA) at the gate
12:37AA 3176 to San Francisco leaves the gate
15 h 09 apart on the timetable, overnight
AA 3176 leaves 15 h 09 after UA 5955 arrives on the timetable: more than half a day, so not a connection we count.