Hi Amr
Yes this is standard behavior. I am surprised why system is not giving this message on sale order level. I think as per standard system should give you this message at both level, sale order and delivery if you have activated credit on both documents. FD will post this value to secure receivable only. If your credit limit used is already 999% and you have activated credit check, system should give you error on sale order level too. Did you get the error only on delivery??
Thank$