Field help (DLVDATSCO) 

This field is only specified in the event of a material product To be sent to the subcontractor.
It contains the expected delivery date at the subcontractor's premises. This date is defined automatically as follows: Subcontract operation start date - Lead time to obtain the materials (information entered in the window displayed by clicking Material details from the Actions icon).

It can be modified as long as the material has not be consumed yet, even partially.

During the modification of this date, the system controls that this date does not correspond to a non-working day or an unavailable day for the delivery date. If this is a non-working day, the date is automatically postponed, otherwise a warning message is displayed.