A Continuity Mailer ... Who Me? Never! Why Not?

"... of the Month Club": different items within a niche, shipped monthly, e.g., red wine. Setup can be open-ended until the customer cancels (usually for herself) or a for a finite number of months (often gifts). All customers receive the same item at the same time.

Auto replenishment: same shipment each delivery. Products commonly are consumables, such as pet food or nutritional supplements. Customers have a unique delivery schedule based on their start dates.