@ ImpactBreaker: Well, yes, 12 would be the month, but I've seen "December 12th". So it can't be meant in that way.
I definitely haven't heard of it being released so much earlier in other places, and I somehow doubt it would be...and besides, as ~K+ said, it's not being advertised as being the 12th. Avex is completely engraining the 15th in our brains.
I just don't get it.