LH 1175 then BA 903 at Frankfurt
Porto → Frankfurt am Main → London Heathrow
Timetable, Frankfurt am Main time
16:15LH 1175 from Porto at the gate
15:00BA 903 to London Heathrow leaves the gate
22 h 45 apart on the timetable, overnight
BA 903 leaves 22 h 45 after LH 1175 arrives on the timetable: more than half a day, so not a connection we count.