FR 6974 then BA 483 at Barcelona
Rome → Barcelona → London Heathrow
Timetable, Barcelona time
22:25FR 6974 from Rome at the gate
18:10BA 483 to London Heathrow leaves the gate
19 h 45 apart on the timetable, overnight
BA 483 leaves 19 h 45 after FR 6974 arrives on the timetable: more than half a day, so not a connection we count.