| To determine order start and finish date (basic procedure) |  |
| To be able to calculate lead times, ERP LN must determine the start date and the finish date of an order. This topic describes the basic procedure that ERP LN uses to do so. Basic procedure Step 1. Determine finish date Starting from the planned requirement date, ERP LN determines the finish date by planning the following lead times backward: The safety time from the Item - Ordering (tcibd2100s000) session (planned with the calendar of the item's enterprise unit). The extra lead time from the Items - Planning (cprpd1100m000) session (planned with the calendar of the item's enterprise unit). The outbound lead time from the Warehouse - Item (whwmd2110s000) session (planned with the item/warehouse calendar). Step 2. Correct finish date for time fence If you do not simulate within the time fence, and the computed finish date falls before the time fence, the finish date is made equal to the time fence. If the time fence is zero, this means that the finish date is reset to the current date. If the Planned Order before Firm/Actual check box in the Items - Planning (cprpd1100m000) session is selected, the following applies: The time fence for production orders is effectively extended to the last firm-planned or actual production order. The time fence for purchase orders is effectively extended to the last firm-planned or actual purchase order. The time fence for distribution orders is effectively extended to the last firm-planned distribution order. If you simulate within the time fence, the finish date can fall in the past. Step 3. Correct finish date for fixed-delivery moment If you specified a fixed-delivery code for the item in the Items - Planning (cprpd1100m000) session, the finish date is set back to the latest fixed-delivery moment before the finish date. In the following cases, Enterprise Planning resets the finish date to the first fixed-delivery moment after the current finish date: The latest fixed-delivery moment before the finish date falls before the scenario start date. You do not simulate within the time fence and the latest fixed-delivery moment before the finish date falls before the time fence. Step 4. Determine start date Starting from the finish date, ERP LN determines the start date by planning backward the effective supply lead time. It is possible that the computed start date of a planned order falls in the past. ERP LN does not correct this date. Step 5. Correct start date and finish date for scenario start date If the computed start date or finish date falls before the scenario start date, it is made equal to the scenario start date. Related topics To compute supply lead-times Purchase lead time calculation Production lead-time calculation in Enterprise Planning Distribution Lead-time Calculation |