To hide out-of-stock and backorder items from subscription alerts, you need to first install Back in Stock Notifier for WooCommerce extension. It can be set up within minutes. Go to WP Admin Panel and select Addify Back in Stock & Price Alert. Now, you need to click on Price Alerts and from its settings enable Hide Price Alert for Out-of-Stock and Backorder Items. For a detailed overview, follow these steps:
1. Install the extension and go to WP Admin Panel > Addify Back in Stock & Price Alert. Now, from the main menu, click on Price Alerts
2. Here you can add subscription box for price alerts and ask users to sign up and get updates related to price changes.
3. In order to hide subscription alerts for out-of-stock items, you need to enable Hide Price Alert for Out-of-stock products.
4. Now, enable Hide Price Alerts for Backorder Products
5. Click on Save
