Offered here is the article M0EAY5 with C2 stepping.
On the web I found that the article M0EAY0 the C1 Stepping has.
The number M0AAY0 came what I found nothing on the net. After consultation with the ASUS Support in Ratingen was told that it ever is here at one of the very first boards with C1 stepping.
The C1 boards are still sold, but are priced roughly at 70-80 euro, so grossly 100 euros less.
Keep your eyes peeled on that you do not pay the full price of an old board.
Amazon has been informed and will clean this up.