// verwijder 'kan nabesteld worden'
add_filter( 'woocommerce_get_availability_text', 'filter_product_availability_text', 10, 2 );
function filter_product_availability_text( $availability, $product ) {

if( $product->backorders_require_notification() ) {
$availability = str_replace('(kan nabesteld worden)', '', $availability);
}
return $availability;
}

// pas backorder tekst aan
function change_backorder_message( $text, $product ){
if ( $product->managing_stock() && $product->is_on_backorder( 1 ) ) {
$text = __( 'Levertijd 3 - 6 dagen', 'your-textdomain' );
}
return $text;
}
add_filter( 'woocommerce_get_availability_text', 'change_backorder_message', 10, 2 );

// pas out of stock aan
add_filter( 'woocommerce_get_availability', 'wcs_custom_get_availability', 1, 2);
function wcs_custom_get_availability( $availability, $_product ) {
// Change Out of Stock Text
if ( ! $_product->is_in_stock() ) {
$availability['availability'] = __('Levertijd langer dan 10 dagen', 'woocommerce');
}
return $availability;
}