BA 391 then BA 990 at Heathrow
Brussels → London → Berlin
Timetable, London time
16:15BA 391 from Brussels at the gate
16:00BA 990 to Berlin leaves the gate
23 h 45 apart on the timetable, overnight
BA 990 leaves 23 h 45 after BA 391 arrives on the timetable: more than half a day, so not a connection we count.