UA 1853 then BA 280 at LAX
Cleveland → Los Angeles → London
Timetable, Los Angeles time
20:27UA 1853 from Cleveland at the gate
18:00BA 280 to London leaves the gate
21 h 33 apart on the timetable, overnight
BA 280 leaves 21 h 33 after UA 1853 arrives on the timetable: more than half a day, so not a connection we count.