In the past and current (Oct 2013) CIM Guides it documents the expirationDate field as having a format of YYYY-MM.
Is the format that strict, or do you interpret other values?
I find it interesting that when expirationDate is returned in a CustomerPaymentProfileMaskedType it is XXXX and not XXXX-XX or XXXXXXX. Similarly when using the Hosted option and editing payment information it appears as **** and prompts for mm/yy*. Finally the Manage payment and shipping information form shows the expiration date in the clear as, for example, 05/14 for a May 2014 expiration and if you click Edit it shows again 05/14 and gives a format hint of (mm/yy). Those inputs match the expiration stamp of the cards in my wallet. I don't have a single one that lists the full year.
* Yes, the cardNumber, no matter the origional length, is also masked down to XXXXNNNN where the N's are the last four digits so the number of X's doesn't indicate the actual stored value. Maybe the minimum mask size is four X's, used in "this field is masked" tests, and 2014-05 condensed to 0514 is completely masked by virtue of the four X rule.
Thank you for your time,
