BA 1451 then VS 11 at Heathrow
Edinburgh → London → Boston
Timetable, London time
17:30BA 1451 from Edinburgh at the gate
17:20VS 11 to Boston leaves the gate
23 h 50 apart on the timetable, overnight
VS 11 leaves 23 h 50 after BA 1451 arrives on the timetable: more than half a day, so not a connection we count.