A pharmaceutical distribution center consists of A-frames for frequently demanded prescription and OTC drugs, gravity flow racks for less demanded items, and static racks for slow moving items. The A-frames and racks are restocked during the day while orders from hospitals and pharmacies are being placed. At night, orders are picked, assembled, sorted, and checked. By dawn, delivery trucks leave the DC towards the customers to deliver the orders.  

A major pharmacy has been added as a client. As a result, the management of the DC has proclaimed that the trucks are consistently leaving the DC later than their scheduled departure times, overtime cost is increasingly above target levels, and emergency restocks are becoming more frequent. What should they do to meet their target departure times and reduce their overtime labor cost? Should they rethink which products (and in what quantities) should go on the A-frames? Should they plan their stocking levels and locations based on seasonal demand (e.g. flu season or allergy season)? Should they implement a flexible labor policy to shift pickers across zones based on nightly picking demand?