Blended fulfilment sits at 2.4 days with an 89% on-time rate. That headline looks tolerable. It isn’t. West Coast fulfilment has degraded from 2.1 days in January to 3.4 days today — a 40% increase in 12 weeks. The blended average obscured it completely. East Coast and Midwest are stable. The divergence started the week of Jan 20 and has worsened every week since.

Customs clearance delays (37%) and carrier handoff failures (29%) account for two-thirds of all late shipments. Both are concentrated on West Coast routes. Three suppliers — B, C, and E — account for 71% of late deliveries. Supplier C has a 32% late rate and a 4.1% defect rate. They stay in the rotation because they’re the cheapest. That tradeoff doesn’t hold.

Cost per order has risen from $4.51 in January to $5.12 today. Annualised at current volumes, that’s $18,000 in unplanned cost.

The blended 2.4-day average masks a three-speed operation. East Coast ran 1.8–2.0 days all quarter. Flat. Midwest: 2.0–2.1 days. Also flat. West Coast is neither.

West Coast started January at 2.1 days. By Jan W3, it jumped to 2.5. That’s the inflection. It’s climbed every week since: 2.7 in Feb W1, 3.0 by Feb W3, 3.4 now. No single event. Just creep. Creep doesn’t trigger alerts. It accumulates.

The blended average rose from 1.97 to 2.4 over the same period. East and Midwest moved a combined 0.1 days. All the signal is in West Coast. The average absorbed it.

Three suppliers drive 71% of late deliveries: Supplier B (13% late rate), Supplier C (32%), Supplier E (18%). The concentration leaves no operational buffer.

Supplier C is the sharpest tradeoff. At $2.20/unit, they’re 35% cheaper than the portfolio average. Reliability score: 68%. Defect rate: 4.1% — three times Supplier A. The cost saving per order doesn’t cover the downstream cost: customer service tickets, re-shipments, churn from SLA misses. That math hasn’t been run.

Supplier D is the benchmark nobody scales: 96% reliability, 0.8% defect rate, 1.6-day lead time. They cost $4.10/unit. The operational overhead they eliminate closes the gap. They handle the smallest share of West Coast volume. Shift allocation.

Supplier C’s $2.20/unit price looks like a saving. It isn’t. At 32% late rate on West Coast lanes, every third shipment is a customer service incident. The $1.90/unit gap between Supplier C and Supplier D doesn’t cover the re-shipment cost, the SLA credit, or the churn risk from a late delivery.

Supplier D is under-allocated on West Coast routes. They have the best reliability and the smallest share of the problem region. That’s not a coincidence — it’s a capacity decision that hasn’t been updated since West Coast volume grew. Reallocate before the next SLA breach does it for you.

$0.61 doesn’t sound like much. Annualised at current volume, that’s $18,000 in unplanned cost. The creep is steady — $0.05/week — and shows no sign of plateauing. At this rate, cost per order hits $5.72 by end of Q2.

The driver isn’t supplier pricing. That’s been flat all quarter. It’s the operational overhead of late shipments: expediting, re-routing, customer service time, SLA credits. Fix the late shipments and the cost curve flattens. Don’t fix them and the cost creep becomes the new baseline.

1. Fix the customs clearance process first. 37% of all late shipments, concentrated on West Coast routes. This isn’t a supplier problem — it’s a documentation or broker problem. Audit the last 30 customs delays. The pattern is there.

2. Cap Supplier C’s West Coast allocation at 20%. Their late rate on West Coast lanes exceeds the 32% portfolio average. Run the lane-level breakdown. Above 40%, pull them off West Coast routes entirely.

3. Expand Supplier D capacity for West Coast routes. Only supplier with sub-2-day lead time and 95%+ reliability. The $0.90/unit premium pays for itself in reduced re-shipments and SLA compensation.

4. Add a regional SLA alert. West Coast degraded for four weeks before the monthly review caught it. A weekly regional breakdown with a >2.5-day threshold surfaces this in Jan W3, not March.

If customs and carrier issues stay unfixed, West Coast fulfilment hits 4.0 days by mid-Q2. The creep rate is 0.11 days/week and shows no sign of plateauing. At that trajectory, the blended average crosses 2.8 days and on-time rate drops below 82% — a level that triggers SLA penalties with two enterprise accounts.

Cost per order is climbing at $0.05/week. Unchecked, that’s $5.72 by end of Q2. Annualised: $28,800 in unplanned cost — $10,800 more than the current run rate.

Shifting Supplier D onto West Coast routes changes the SLA picture. Supplier D’s 1.6-day lead time and 96% reliability on a lane they barely serve today means the West Coast average drops from 3.4 toward 2.6 days even with customs delays unresolved. It doesn’t fix the root cause. It buys time to fix it. Without that buffer, Q2 is a damage report, not a performance review.