BA 391 then BA 928 at Heathrow
Brussels → London → Hannover
Timetable, London time
16:15BA 391 from Brussels at the gate
15:45BA 928 to Hannover leaves the gate
23 h 30 apart on the timetable, overnight
BA 928 leaves 23 h 30 after BA 391 arrives on the timetable: more than half a day, so not a connection we count.