Could the notice be better drafted before posting it on the website?

I happened to visit a a large local service company website and this announcement page was posted there. I took a screenshot and produced it here for discussion. The name of the company was erased to protect its privacy. I think it was thoughtful of the company to post such an announcement to inform its customers of the web service interruption. The reason is: Not every company does it!

However, there were some mistakes which I thought the company could have spotted and corrected before posting it on the website. The "11st" and "12nd" are wrong; they should be correctly written as 11th (eleventh) and 12th (twelfth) respectively. The correct usage should be 1st, 11th, 21st, or 31st and 2nd, 12th or 22nd. It is generally acceptable to have the date written simply as 11 July 2009, unlike in some legal or contractual documents where it is usually written as "on the 11th day of July 2009", for example.

Not only that, I feel that more effort could have been put into the writing of this annoucement for its millions of customers. Obviously, the same message could be written in many other ways. For the purpose of learning, I am taking my liberty to provide an alternative version to the one that was posted.

"Thank you for visiting our website. The website will be closed for system upgrade from 11pm, 11 July 2009 to 2am, 12 July 2009. We apologise for any inconvenience at your end and appreciate your understanding. We look forward to serving you again soon."