The schedule lines setting for the MRP planning run is sometimes misunderstood which means it can get little consideration when planning the MRP runs. Most times the default setting, 3 – Schedule lines, is the selected option as it appears to be the safe thing to do.
Schedule lines refer to delivery schedules based upon on scheduling agreements. Thus, if you have a material which is procured on a subcontracted basis, you can prearrange the deliveries by using those procurement schedule agreements. The source list is where the vendor and scheduling agreements are maintained for relevance for material planning. So what exactly does this setting afford an organization for their planning run? Well, let’s start with the available options and provide a more simplified explanation of each of the available options.
The first option, 1 – No schedule lines, will not plan scheduled deliveries based upon the purchasing scheduling agreements, but will instead solely use the planned delivery time from the material master and backward schedule from the requirements dates. Option number two, 2 – Schedule lines in the opening period, will afford delivery scheduling determination based up those scheduling agreements for those that occur within the opening period as defined by the material’s schedule margin key. The third option is to include the scheduling agreements versus the planned delivery time throughout the entire planning horizon.
There is no correct answer in which option to choose, but the safe bet is still the default of 3 – Schedules lines. The reasoning is that if scheduling agreements are used then MRP will pick those delivery dates, otherwise, it will utilize the planned delivery time from the material master.