IB 717 then BA 928 at Heathrow
Madrid → London → Hannover
Timetable, London time
14:55IB 717 from Madrid at the gate
14:50BA 928 to Hannover leaves the gate
23 h 55 apart on the timetable, overnight
BA 928 leaves 23 h 55 after IB 717 arrives on the timetable: more than half a day, so not a connection we count.