This is an excellent offer for anyone wanting to transition from BAEC to Finnair. There are some keenly priced flights from London to Seoul booking fully flex (which, of course, yields more avios/tier points with higher base fare) so there is little risk if you change your mind as you can get a full refund. Business flex also provides free seating assignment/lounge access without pre-existing status. It looks like two return flights in business flex from London to Incheon at ~£2.5k each is enough to get to Platinum.