I'm seeking a clue regarding something we're seeing on lead times on planned purchase orders.

We have many purchased items with established lead times. In one case in particular, the item has both an Item Purchase Data record and an Item Production Data record and both records have the same lead time.

Yet Simulate Orders produces planned purchase orders with the same start and finish date - as if there is no lead time on the item.

I'm assuming something is set up incorrectly on these items but I'm hoping someone can lend me a clue.

Mick,

Have you got Item Supplier records for these items and if so is the Supply Time set correctly in there? If I remember correctly, EP will use Item Supplier Info ahead of Item Purchase Data.
If not, it may be worth checking that the calendar is correctly set-up for the Blank Availability type.

Martin.