Pre-orders and out-of-stock items are common states in an e-shop, and the way they are handled decides whether you lose or capture demand. The worst option is to remove the product page – the page had traffic and links, which are then wasted, and the customer ends up on an error page. It is better to keep the page, clearly state that the item is not in stock, and offer three options: a restock notification after entering contact details, a pre-order with a stated date, or alternative products. If the product will never return, redirect the page to the closest similar one, not to the homepage. In the feed and in structured data, availability must match reality, otherwise you pay for clicks on goods you do not have.
See also: Availability and Delivery Time, Soft 404, Product feed.
