Managing is getting something done, stabilizing existing processes, controlling and correcting deviations to ensure quality and reliability.
Leadership is about doing something new or better, whether a simple process improvement or a transformation. It is more about reframing for improvement. It likely calls upon people to learn new skills and shift beliefs.
Our tendency to ascribe leadership to individuals that hold a formal entitlement as head of a team, group, or function is unhelpful when distinguishing management from leadership as activities with different purposes.
Leadership is not the property of a formal position, but rather an activity that occurs anywhere in the company. A person responsible for such a change is therefore in a leadership role irrespective of title.