BA 581 then BA 229 at Heathrow
Milan → London → Baltimore
Timetable, London time
13:55BA 581 from Milan at the gate
13:50BA 229 to Baltimore leaves the gate
23 h 55 apart on the timetable, overnight
BA 229 leaves 23 h 55 after BA 581 arrives on the timetable: more than half a day, so not a connection we count.