Hmm I don't see it on the main page but I got it in an email this morning. It says no code needed. Let me link you right to the page it brings me to:
https://orders.persnicketyprints.com...eid=8bfc3cefb7
If I add the pages to my cart instead of being credits it does show on sale that way as well.
Hope this works for you! If not, maybe I can forward you the email and try it that way?!