The Opportunity We re looking for an experienced Manufacturing Planning Manager to play a key role in a major SAP S/4HANA transformation programme within the Defence sector. This is a high-impact position where you will act as the UK Subject Matter Expert for Planning and Control within Manufacturing. You will help define, validate, and implement future-state SAP S/4HANA processes while ensuring business continuity throughout the transformation. This role sits at the heart of manufacturing operations and digital transformation offering real influence over how planning and execution processes operate long-term. What You ll Be Doing Leading the definition and validation of future-state SAP S/4HANA Planning and Control processes Reviewing and signing off detailed process design documentation Driving harmonisation of manufacturing planning processes across international teams Leading system testing activities within your functional area Supporting data migration and data cleansing activities Working closely with change and training leads to support adoption Engaging senior stakeholders across UK and European sites Ensuring continuity of manufacturing planning operations during system transition What We re Looking For Strong experience using SAP ERP in a manufacturing environment (Planning and Control focus) Deep understanding of manufacturing planning processes (MRP, production planning, execution control) Experience in SAP S/4HANA programmes or ERP tran