I just got a heritage x from evo a couple of weeks ago... same thing blue base white eagle logo. I called NS and they said they were pretty much done with production for the year but evo placed an order... since they were getting ready for next year they made the boards for the order (about 50) with this different base. He claimed they were extra custom... I'm not really sure about that, but I actually prefer the look of my base to the standard heritage!
Man I wish you hadn't posted that...I got a Heritage from EVO recently but it had the standard base. I like yours better.
I do like the top sheet of the 10/11 as compared to the 11/12 version though and I guess that is what we see. Really enjoy the board.