How Item Lead Time Affects ATP

To determine when supplies of purchased or manufactured items could be available when no supply (or not enough supply) is expected for the item in the business unit, the ATP function calculates availability based on the item's lead time.

Purchased Items

If PeopleSoft Purchasing is installed, the standard lead time value on the Purchasing Attributes page defines the standard lead time required to purchase an item. For buy items for which no future supply (or not enough supply) is anticipated, the promise date is calculated as the current date, plus this lead time. If PeopleSoft Purchasing is not installed, the lead time for buy items is calculated using the Replenish Lead Days value defined on the Define Business Unit Item - Inventory: Replenishment page as the current date, plus the replenishment lead time.

Manufactured Items

Fixed lead time and variable lead time values on the Define Business Unit Item - Planning: Fences/Lead Time page define the lead time required to manufacture an item. For make items for which no future supply is anticipated, the promise date is calculated using the following formula: current date + fixed lead time + (order quantity in the standard UOM x variable lead time). The resulting date is rounded up to the next day.