BA 198 then BA 546 at Heathrow
Mumbai → London → Bologna
Timetable, London time
18:20BA 198 from Mumbai at the gate
18:10BA 546 to Bologna leaves the gate
23 h 50 apart on the timetable, overnight
BA 546 leaves 23 h 50 after BA 198 arrives on the timetable: more than half a day, so not a connection we count.