Consistently display the stock status on the Single Product page in WooCommerce

functions.php

add_filter( ‘woocommerce_get_availability’, ‘custom_override_get_availability’, 10, 2);

// The hook in function $availability is passed via the filter!
function custom_override_get_availability( $availability, $_product ) {
if ( $_product->is_in_stock() ) $availability[‘availability’] = __(‘In stock’, ‘woodmart’);
return $availability;
}