So I have an iCloud Apple ID which I use to purchase all my content via apple. As far as I can tell, I can't change my Apple ID to my gmail address. Correct? If that's the case, is there any way I can change the way my billing invoices are sent to me, so that whilst I continue to purchase under my @icloud.com Apple ID (I have iTunes Match and about 6/7 years worth of purchases under it...) I can have them sent to my gmail address to allow for archiving/labelling/filing with all the rest of my invoices and mail. I suppose the other alternative is to just forward them, but that's an extra step I'd rather avoid if at all possible. Sorry for the randomness of this question.