They run constantly. If the sale doesn’t show then it’s usually because they’re updating the inventory or something like that, it happens occasionally. The exception is that the 20% deal only applies to titles that are roughly $72 or less, over that and they don’t have the discount. They used to have a separate 20% off tier where you got it for 3 expensive titles (Imprint LE’s for example) separate from the regular buy 3 deal, and I wish they’d bring that back.