A system for replenishing a pick face includes a storage and retrieval machine (SRM) that traverses an aisle of a warehouse and monitors a replenishment position of each pick location of a pick face. The SRM transmits a message to the system indicating which ones of the replenishment positions are empty. The SRM delivers a replenishment load to a pick location that is indicated as empty in the message. Each pick location includes a flow lane configured to direct the motion of package loads sliding down to a picking position of the pick face. The flow lane includes a lever arm assembly that constrains and brakes the motion of package loads sliding down the flow lane. A bar stop of the lever arm assembly constrains a replenishment load, while a retainer bar of the lever arm assembly constrains a forward load. The replenishment load is behind the forward load.