How to fix the filter in the admin panel after adding a custom balance status?

Question

WooCommerce

WooCommerce version: 3.8.1
Added a custom field to stock_status through a filter:

add_filter(
  'woocommerce_product_stock_status_options',
  'ec_add_custom_product_stock_status_option'
);
function ec_add_custom_product_stock_status_option ($arr) {
  $arr['fororder'] = __( 'Доступно для заказа', 'woocommerce' );
  return $arr;
}

Everything works, except for the actual filter of these statuses in the admin panel on the "All products" page.
It shows "No items found" even for the instock option.
For new products, and if I manually, according to a new one, set the status of the balance in the product, this product, miraculously, will fall into the filter. I just don’t understand, maybe you can somehow update the statuses for all products?
What could be the problem?