We have a requirements to summarize picking list by customer and by delivery date. Currently we can summarize the picking list only by the limited fields available in summary update options. Enabling option to include any fields from the data source into the "Set up summary update options for picking lists" will cover every customers requirement to summarize the picking list according to their business process. Path : Accounts receivable > Setup > Accounts receivable parameters > Summary update > Summary update parameters > Picking list > set up summary update options for picking lists