as I had spotted it at the Patek Salon in London 4 years ago. It was a cancelled order for a special customer so this could be the only 3878J with a Patek seal since it was discontinued in 1998. My AD in the UK has kindly kept it in its safe for the last four years and it will finally be shipped out to me in time for my 60th birthday in August! Yes, a present to myself planned four years ago!