BA 818 then SK 1790 at Copenhagen
London Heathrow → Copenhagen → Tallinn
Timetable, Copenhagen time
23:25BA 818 from London Heathrow at the gate
22:55SK 1790 to Tallinn leaves the gate
23 h 30 apart on the timetable, overnight
SK 1790 leaves 23 h 30 after BA 818 arrives on the timetable: more than half a day, so not a connection we count.