Sorry,
I got to the bottom of the matter in the meantime and contacted Paul McCartney this morning. I asked him if he didn't miss his watch. He is so happy to get it back from me and promised to pay finder's wages.
It was an accident that the 9411 was on my wrist when I decided to head to the lake for kiting; but in the end, well worth it considering it鈥檚 one of my favorite spots in the world right now: