I know nothing specific about restaurant.com, but all shopping portals (nothing specific to Priority Club, since they all work the same, may even all be implemented by the same company behind-the-scenes?) can be very slow (months!) when you make a purchase that has any capability for a return. Basically, if you buy a physical product that's theoretically returnable, many stores wait a month or two to make sure you're not going to return it before they do whatever it is that makes the miles or points get issued for the purchase. (And then at that point, they may only send the data back to Priority Club or wherever on a weekly, biweekly, or even only monthly basis, so if they "miss the window", it can be another sizeable delay.)

That's the reason so many promos have "6-8 weeks after end of promo" or "8-12 weeks after end of promo", etc, language in them (I don't remember offhand what this promo has), to allow for such delays from partners.

I can tell you that a purchase I made at Office Max (not through the shopping portal, but through Priority Club's specific Offixe Max link, which counts as a different partner than a shopping portal partner), posted a week or two after I made the purchase. But also, scarily, it posted with the wrong date (the date of posting, not the date of the purchase or the date of shipping!). Now, in my case, I have weeks to go, but I could see a problem if someone used OfficeMax during the last week or two and then they played the tirick of posting the purchase with a date that was past the end of the promo!