Add filter for customer reference

Hello, thanks for the great plugin!

I am working with a client that wants to programmatically change the customer_reference when an order is created.

I modified sendle-shipment-booking.php @ line 286 to add:

//Allow plugins & themes to change the customer reference.
//Reference will appear on the label for parcel identification. It must be under 255 characters in length. (Optional)
//https://api-doc.sendle.com/#parcel-details
$customer_reference = apply_filters('ossm_filter_customer_reference', $order_id);
if ($customer_reference && strlen($customer_reference) >= 255) $customer_reference = $order_id;
ossm_logActions("[orderid:".$order_id."] ossm_filter_customer_reference Customer Reference : ".$customer_reference." ");

And below that in the $json variable to include

"customer_reference": "'.$customer_reference.'",

In a different plugin, I am doing the following:

function codeparachute_filter_customer_reference($order_id) {
    $order = wc_get_order($order_id);
    return $order->get_name();
}
add_filter('ossm_filter_customer_reference', 'codeparachute_filter_customer_reference');

Questions for the maintainer:

1. Is this the appropriate way to modify the customer reference?
2. Can this filter be added to the plugin?