I am working on a credit card processing system for an eCommerce website. We do full amount authorization during checkout and settlement just before delivering the goods (7-14 days).
Question: Is there a way to get the "auth expiration date" as part of the authorization response from the issuer?
No. You can get an authorization but no expiration date is given with it. Typically it is 30 days but it doesn't have to be that long. But if you're charging within 14 days you should be fine as they are never shorter then that.