However, you will need proof that you purchased last seasons black shirt at the full price. (Receipt or Credit Card statement etc).
Covsupport understands that supporters are able to bring along their old away shirt to the club shops and have the label 'cut' or marked to indicate that they'd used their £10 discount towards the new one.
Covsupport recommend that you wait until after the transfer window closes on August 31st before having the name and number of any current player put on the back of your shirt.