Yesterday I went for a walk in Lisbon and had no major problems, even putting my iPhone 6 in left pocket. I was quite surprised, it seems to happen only on wide open areas and inside when I leave the room where my Macbook is.
My SN is 0514000119 and I have this other info on box, 2014118REV01, I think it's the manufacture day.
Interesting, I didn't notice the revision number. Mine is 20141118REV01, so produced 10 days later maybe, or did you just leave out a "1" :P ?.
Would be interesting if people posted a short comment with their revision number, if they have BT issues and if so how severe. Especially those with no issues whatsoever.
On a side note, I upgraded to Android Lollipop 5.02 yesterday, will report back after a few days use and experimenting with settings.