In the context of the supply chain, PDP stands for "Production Master Plan". The PDP is a long-term plan that identifies production goals, inventory levels, delivery times, and the capabilities and resources needed to achieve those goals. The PDP serves as a guide for short-term production planning by providing an overview of production needs over a period of time, often a year. PDP is used to align production with demand, reduce inventory costs and improve supply chain operational efficiency.
Here is a more detailed article (in french) on the subject : Pilotez votre chaîne de production grâce au PDP