If you are shipping Items with this Offer and want to adjust any shipping logic, under the Offer Configuration is where you will do this.

A shipping frequency is how often and when the physical product is being sent to the fulfillment center to be shipped to the customer. In the case of a prepaid offer, a single charge could create and schedule multiple shipments to be sent in intervals. Or simply delay the shipment from posting to the warehouse for X hours, to allow for any order updates.

Custom shipping use cases:

Custom Offer Shipping Price
Prepaid Shipping Rules
Shipping Delays

Fulfillment Defined

Fulfillment Field	Defined	Examples
Shipping Price	If applicable. If Shipping Profile is set on the Campaign, both Shipping Price and Shipping Profile will be charged. NOTE : making a change to this setting will only apply to transactions that have not yet been scheduled.	Your offer is a recurring subscription and you want th charge $8 every renewal. This will apply at the initial purchase and all subsequent renewals._
Multiple Shipments*	When checked, multiple shipments will be scheduled upon a successful charge. This is used for Prepaid Offers.
Shipment Count*	Define how many shipments should be scheduled upon a successful charge.	A charge occurs and is a 3 month prepaid. This charge will schedule 3 shipments.
Shipment Timeframe*	After determining the timing of the first shipment, establish guidelines for scheduling future shipments. If the available default frequency choices do not match the required shipping schedule, develop a customized timeframe.
Fulfillment Delay	The number of hours to delay sending the shipment to fulfillment after a successful charge.	This is done to alleviate shipping anything where a customer instantly cancels/voids their order.

*Used for Prepaid Offers