I cannot fault Gray Nics to be honest - I actually won a bat via AOC last year - a Maverick F1 Players, but it was too heavy, so I had the weight reduced - the service and communication was superb and it is a very decent bat indeed. Quite softly pressed. Had the sorbo handle option too - as I find GN handles far too thin and I'm a two and a half grips man - much better.
However, back to the question - contact the retailer / bat maker and express your concerns. All you can do really. It is a difficult one, is it fit for purpose? Or, when does it become fit for purpose? Difficult because a bat has the concept of knocking / playing in. I think any manufacturer would probably be reasonable and if you as the consumer are not satisfied with any product, you are entitled to complain and recieve a refund, replacement or credit note.