You may be wondering, can we have a ReStock Alerts button on products that can be pre-ordered?
First of all, let us explain what we mean by pre-order products:
When you check the "continue selling when out of stock" box in your Shopify admin, this product can be sold even when the stock is 0, in other words, pre-ordered. This option can be found in your Shopify admin > Products. By selecting each product and then its variants you'll see it like this:
When this is on, it means your product can be pre-ordered, and in this case, you should activate a feature to have the "Notify me" button on these products too. You can find it on your panel> Widgets > Advanced > Show the "Notify me" button on the pre-order product pages.
By enabling this feature you can have the "notify me" on the pre-order products too.