4Y 803 then BA 903 at Frankfurt
Bari → Frankfurt am Main → London Heathrow
Timetable, Frankfurt am Main time
20:104Y 803 from Bari at the gate
15:15BA 903 to London Heathrow leaves the gate
19 h 05 apart on the timetable, overnight
BA 903 leaves 19 h 05 after 4Y 803 arrives on the timetable: more than half a day, so not a connection we count.