First I told them I wanted to return it for a full refund, but they answered that given that the reason is that I dont like the product the returns costs goes on my part, wich I see unacceptable.
I replied that the real reason was that I expected (reasonable so IMHO) to receive one of the new batch, but that I can agree to get a substitution with no aditional costs on my part, or, if not possible, to keep the product and get a refund.
Still waiting for their reply.