Autonomous delivery drones operating in GLMZ's logistics network began routing packages through a decommissioned river corridor in late 2224. The corridor — a stretch of the Chicago River that was sealed and diverted during the city's restructuring — is not on any active navigation chart. Drone pathfinding algorithms should not be able to route through it. The corridor does not exist in the map data. And yet, beginning November 14, 2224, an average of thirty-seven packages per day took a detour through the sealed waterway, adding between two and nine hours to their delivery time. No customer complaints were filed. The packages arrived. They arrived different.

The routing anomaly was discovered by logistics analyst Kenji Abara during a delivery-time optimization review. Abara traced the affected drones' GPS logs and found they were entering the sealed corridor through an access point that infrastructure records show was welded shut in 2203. Physical inspection confirmed the access point is, in fact, welded shut. The drones are going through it anyway. Abara's report describes this with the restraint of someone who understands his career depends on not saying what he actually thinks: "The drones appear to be navigating through a physical barrier that multiple inspection teams have confirmed is intact. This is noted for further review." Further review has not occurred.

The packages that transit the river corridor arrive with subtle alterations that recipients consistently fail to notice until they are pointed out. Shipping labels are repositioned — moved from the standard upper-right placement to locations that are, upon analysis, more structurally sound for the package's dimensions. Contents are rearranged. A box of medical supplies arrived with the items sorted by frequency of use rather than by the packing algorithm's default weight-distribution pattern. Electronics shipments arrive with cables coiled more efficiently. Food deliveries are reorganized so that temperature-sensitive items are insulated by ambient-stable ones. The changes are small, practical, and impossible. The drones do not have manipulator appendages capable of opening packages.

One recipient — a home healthcare aide named Fatima al-Rashid — found a handwritten note tucked between sealed sterile bandage packs in a medical supply delivery. The package had been sealed at the distribution center and showed no signs of tampering. The note was written on paper that chemical analysis identified as cotton-fiber stock that has not been manufactured since 2187. The handwriting was fluid, unhurried, and written in ink that contained trace elements of river sediment. The note read: "You needed this first." Beneath it, a second line: "The one on the bottom left is expired. Check the date." The bandage pack on the bottom left was, in fact, three days past its sterility date. It had passed the distribution center's automated quality check. The note had not.

The GLMZ Anomaly Documentation Project has tagged the river corridor as an active anomaly zone. Drones continue to route through it. Packages continue to arrive adjusted. Kenji Abara, who discovered the pattern, has stopped filing reports about it. When asked why, he said the packages arrive better than they left. He said the corridor is performing a service. He said he doesn't know who or what is doing it, but he recognizes care when he sees it, and he is not going to be the person who makes it stop.