BA 487 then AI 2018 at Heathrow
Barcelona → London → New Delhi
Timetable, London time
21:35BA 487 from Barcelona at the gate
21:05AI 2018 to New Delhi leaves the gate
23 h 30 apart on the timetable, overnight
AI 2018 leaves 23 h 30 after BA 487 arrives on the timetable: more than half a day, so not a connection we count.