AA 1259 then VS 118 at Miami
Boston → Miami → London
Timetable, Miami time
11:12AA 1259 from Boston at the gate
23:20VS 118 to London leaves the gate
12 h 08 apart on the timetable
VS 118 leaves 12 h 08 after AA 1259 arrives on the timetable: more than half a day, so not a connection we count.