NETCH, NETPL and NEUPL are three fundamentally different ways to schedule your MRP run:
NETCH – Net Change Planning
NETPL – Net Change Planning within Planning Horizon
NEUPL – Regenerative Planning
SAP is keeping track of changes that are relevant for planning a material (like sales order entry, purchase order entry, stock release, etc.). A planning relevant change signals to MRP that the material should run in the next NETCH or NETPL MRP run. MRP will thus only process those materials that underwent some type of planning relevant change. This can decrease processing time of the MRP background run when compared to processing ALL materials.