We at _________________ are proud to provide you with outstanding workmanship and quality _________________. It is due to our commitment to maintaining these high standards that we have recently realized that it will take us somewhat longer than we originally anticipated to be able to complete your job.
Your job will now be finished by _________________, rather than the original deadline of _________________. Having this additional time to work on your order will enable us to fulfill your specifications exactly.
Thank you for your understanding. We are confident that you will be pleased with the quality of the finished product.