Design Blueprint: Locker Bank Sizing

Design blueprint derived from the source paper (DOI 10.5281/zenodo.24121712): A parcel locker bank fails quietly: it does not queue, it turns parcels away when every compartment is occupied. This paper sizes the bank as an Erlang loss system. Parcels arrive at 15 per day and stay a mean of 2.0 days awaiting collection, an offered load of 30.0 compartment-days per day. To keep turned-away parcels at or below two percent requires 39 compartments, at which the average occupancy is 29.4 compartments (75.4 percent utilisation) — the bank must stand with about a quarter of its compartments empty on average to absorb arrival bunching. Removing five compartments raises blocking Status: DESIGN BLUEPRINT — SIMULATED, NOT MEASURED — NOT BUILT. All numbers are simulated values from the source paper's computation, deposited with this blueprint as compute.py and results.json. AI-use disclosure: Dave, an AI research system, assisted with the computation and drafting under the author's direction; author of record William Alexander Aldred.