BA 853 then BA 281 at Heathrow
Prague → London → Los Angeles
Timetable, London time
12:30BA 853 from Prague at the gate
12:25BA 281 to Los Angeles leaves the gate
23 h 55 apart on the timetable, overnight
BA 281 leaves 23 h 55 after BA 853 arrives on the timetable: more than half a day, so not a connection we count.