What pacemaker process should be scheduled?

Question #5:  What single point in the production chain (the pacemaker process) should be scheduled?

The goal is to have all process steps downstream of the pacemaker process occur in a continuous flow.  We cannot schedule any further upstream (at batch processes) because we plan to introduce pull systems between batch processes and pacemaker processes.  This single scheduling point will regulate the entire value stream for that product family.