Sales are complete once delivery of the product is made and it is accepted by the customer.
The repair of a product under warranty or not under warranty has no impact on the sale. Warranties are not determined by the product specifications, rather by a completely different process and inputs from many areas. Maybe in your company, Alan, but for most of the world, the sale is not considered complete until the warranty has expired. Section 4.19 deals with service for hire or serivce after the warranty.