BA 493 then BA 512 at Heathrow
Gibraltar → London → Lisbon
Timetable, London time
20:45BA 493 from Gibraltar at the gate
19:40BA 512 to Lisbon leaves the gate
22 h 55 apart on the timetable, overnight
BA 512 leaves 22 h 55 after BA 493 arrives on the timetable: more than half a day, so not a connection we count.