VS 355 then BA 746 at Heathrow
Mumbai → London → Geneva
Timetable, London time
15:40VS 355 from Mumbai at the gate
10:30BA 746 to Geneva leaves the gate
18 h 50 apart on the timetable, overnight
BA 746 leaves 18 h 50 after VS 355 arrives on the timetable: more than half a day, so not a connection we count.