Looking back at the original post by rebecca-smiles, it clearly says ATC but I think it was misdirected by someone who thought ATC's and ACEO's were the same.
I guess anyone could make this mistake if they don't know the history of the art form, in practice i.e in the construction, the two cards are the same, same size, etc. but it's the principle of not selling that turns an ATC into an ACEO.
Colly