Board Thread:General Discussion/@comment-4916403-20120918105640/@comment-5498755-20120918112740

October 6th seems to be the date. I support this from " According to the site, the air date attached to the Episode 1 photos is Week 41 (6-12 October by BBC's week count) http://merlin-network.livejournal.com/357457.html.

It seems to me they know the date since they attached the promo pictures with it. But for all I could know the "site" could be false also.