2.4.1.1: Reviewing Customer Requirements
Looking at the SQF Edition 8 Quality Code 2.4.1.1: The requirements and expectations of customers and final consumers shall be continually reviewed to ensure the accuracy of specifications and the ability to supply to customer needs. A full review of customers' expectations for product and delivery shall occur at least annually.
What have other's done for this requirement?
I would look at reviewing customer complaints. Your process capability data will tell you if you are meeting your customer specifications. You would also look at customer orders/sales and fulfillment of orders.
We also include annual review of specifications.