A Chinese export company made a transaction of apples with a foreign company. It’s stipulated “second-class apples” in the quality terms on the contract of sales and letter of credit. However, they found the second-class apples had been all sold out as when they began to arrange the shipment. As a result, the company switched to the delivery of “first-class apples”, and the invoice stated that “the price of the first-class apples is the same as that of the second-class”. Question: Are there any risk in doing so?