Dear Mr. Lee,
Regarding to your request of shipping date changes, I have to inform you that it might take some effort for me to discuss with our shipping supervisor. On July 27 you have confirmed that you prefer the ETA to be 1st week of September, so I have arranged the shipment, and our factory has already scheduled the producing process.
Please be noticed that we also have other on-going orders which needed to be shipped at the same period of time (August 19-26). So I will have to negotiate with our producing department in order to make the change happen. So may I remind you that once we have the confirmation of shipping advice, we normally will have to stick to the schedule. So please allow me some time, and I will get back with you ASAP. Thank you for your understanding.