FR 574 then FR 8231 at Barcelona
Bologna → Barcelona → London Stansted
Timetable, Barcelona time
11:20FR 574 from Bologna at the gate
07:30FR 8231 to London Stansted leaves the gate
20 h 10 apart on the timetable, overnight
FR 8231 leaves 20 h 10 after FR 574 arrives on the timetable: more than half a day, so not a connection we count.