DL 1 then BA 580 at Heathrow
New York JFK → London → Milan
Timetable, London time
08:05DL 1 from New York JFK at the gate
07:10BA 580 to Milan leaves the gate
23 h 05 apart on the timetable, overnight
BA 580 leaves 23 h 05 after DL 1 arrives on the timetable: more than half a day, so not a connection we count.