Payment Run Optimization — Times and sequences payment collection for maximum success — picking retry windows, routing across processors, batching debits around bank cutoffs. It sits between invoicing and the payment layer, and its lift shows up directly in involuntary-churn numbers.
Payment Run Optimization lives in the Rate & Bill phase of Fulfill & Bill — the stage where you activate what was sold, meter what's used, bill it right. In the corpus tool index this phase maps to the Billing and Paymentscategories.