What is the difference between Actual Ship Date and Actual Fulfillment Date?

Summary:

What is the difference between Actual Ship Date and Actual Fulfillment Date?

Content (please ensure you mask any confidential information):

Actual Fulfillment Date (the date when a shipment is delivered and update the corresponding fulfillment line) should be the same as SAD Date because SAD is what the GOP is calculating as the most accurate promise-able date. And we are promising Deliveries based on SAD. The example provided below has got SAD not aligning with the Actual Fulfillment Date (AFD). We need some clarity there, what are the scenarios where the 2 wont line up and should we now start using AFD instead of SAD for customer delivery notifications?