AI 129 then BA 492 at Heathrow
Mumbai → London → Gibraltar
Timetable, London time
11:05AI 129 from Mumbai at the gate
08:10BA 492 to Gibraltar leaves the gate
21 h 05 apart on the timetable, overnight
BA 492 leaves 21 h 05 after AI 129 arrives on the timetable: more than half a day, so not a connection we count.