Con
Yet another WordPress dev
//output with add to cart button
add_action( 'woocommerce_after_add_to_cart_form', 'custom_notice_for_backorders_allowed' );

function custom_notice_for_backorders_allowed() 
    {
        //instantinate product object
        global $product;
        
        //check if backorders are allowed
        if ( $product->backorders_allowed() ) 
           {
            ?>
            Backorders allowed: Put some text and <a href="#">links here.</a>
            <?php
        }
        
    }


//output after product title
add_action( 'woocommerce_single_product_summary', 'custom_notice_for_backorders_not_allowed' );

function custom_notice_for_backorders_not_allowed() 
    {
        global $product;
        
        //check if backorders are not allowed
        if ( ! $product->backorders_allowed() ) 
           {    
               ?>
            Backorders not allowed: Put some text and <a href="#">links here.</a>
            <?php
        }
        
    }