Overview

Amazon is automatically widening the delivery windows shown to shoppers on every Fulfilled by Merchant (FBM) listing in the UK. The change takes effect while Royal Mail workers stage walkouts on 26 and 31 May and on 8 and 9 June, with the possibility of additional strike days. Sellers should care because the extended promises protect their performance metrics from strike‑related delays, giving them leeway to ship orders without risking account health penalties.

Key Points

• Extended delivery windows — Amazon will display longer estimated delivery dates for all UK FBM offers, adding up to several extra days during strike periods.
• Performance safeguards — Amazon pledges to work with sellers to prevent strike‑induced late‑delivery marks from harming their account health scores.
• Confirmed strike dates — Royal Mail has scheduled walkouts on 26 May, 31 May, 8 June and 9 June, and may add further dates if negotiations stall.
• Obligation to ship — Sellers must still process and dispatch every order they receive; the platform only relaxes the customer‑facing promise, not the fulfilment requirement.
• Carrier diversification urged — Amazon recommends adding backup carriers such as DPD, Evri, DHL or UPS to mitigate reliance on Royal Mail.
• Cancellation‑rate warning — A surge in order cancellations during the strike can still damage the cancellation‑rate metric, so sellers should aim to fulfil rather than cancel.

How Delivery Promise Extensions Work

1. System‑wide window adjustment — Amazon’s backend automatically adds extra days to the “Estimated Delivery” field for all UK FBM listings. For example, a product previously promising delivery by 3 May will now show “by 6 May” during the strike window.
2. Real‑time monitoring — The platform continuously checks Royal Mail service alerts. If a carrier reports a delay, Amazon may further extend the window for affected SKUs, ensuring the promise stays realistic.
3. Metric shielding — Late‑delivery incidents that occur because of the extended window are excluded from the Late‑Shipment Rate calculation. A seller whose parcels arrive on the original date but after the new promise will not receive a penalty.