Support other channels like Facebook and Instagram for pre-order

If I am selling on other channels like FB or IG , will the pre-order function show through? Right now I am using a preorder app which only replaces my add to cart button with a pre-order button and tags it. When it shows up on other channels though (selling despite no inventory), then it looks like it is available on other channels, so people buy, is not tagged and it looks like it should be delivering as in stock!