How to Audit Missing WooCommerce Restock Notifications

# How to Audit Missing WooCommerce Restock Notifications A product moving from out of stock to in stock does not prove that every waiting customer received a notification. The stock transition, subscriber list, queue or cron worker, and email attempt are separate facts. Audit them in that order. ## Confirm the transition Record the product and variation, the old and new stock states, the transition time, and the plugin responsible for the waitlist. A quantity edit that never changed the stock status may not trigger the same hooks as a true out-of-stock to in-stock transition. ## Confirm an expected notification existed Check that eligible subscribers existed before the transition and that the waitlist plugin was enabled for the exact product or variation. Exclude unsubscribed, invalid, or already-notified entries according to that plugin's documented rules. ## Follow the email evidence Look for a corresponding `wp_mail` attempt after the transition. Compare time, safe subject preview, recipient hash, result, and source signature. If no attempt exists, investigate the waitlist trigger and scheduled jobs. If an attempt failed, inspect transport logs. If an attempt succeeded, final inbox delivery remains the mail provider's responsibility. ## Use a deploy blocker Block a release when a tested restock creates eligible subscribers but no matching attempt, when one subscriber produces repeated matching attempts, or when customer data appears in diagnostic output. Do not treat a screenshot of a green dashboard as event-level proof. Mail Guard OS records the transition and safe attempt evidence, then raises a missing-expected finding when the configured grace period expires. [Review Mail Guard OS](https://vamaolabs.com/products/vamao-mail-guard-os) or follow the [Mail Guard reference](https://vamaolabs.com/docs/vamao-mail-guard-os/reference).