AA 108 then BA 546 at Heathrow
Boston → London → Bologna
Timetable, London time
07:00AA 108 from Boston at the gate
19:25BA 546 to Bologna leaves the gate
12 h 25 apart on the timetable
BA 546 leaves 12 h 25 after AA 108 arrives on the timetable: more than half a day, so not a connection we count.