Correct my sentence structure

I already sent due date changes to my customer. But due to some reason, I am able to meet the due date, so again asking due date change request to my customer. Please check the sentences below and correct me if am wrong:

I apologize for the delay. The technical edited file actual due was 1st August, then again we requested to you due date changes on the same process by 1st October. Due to refinement, the technical editing process needs few more time extension. However, I wish to inform that there is due date changes in this process, so would like to request that you the technical edited files will reach you by 30th October for your review. The reviewed files can be sent back to me by 14 November, if this date is not comfortable for you kindly let me know your review completion date, accordingly we will adjust our internal process timing. I am sure that other process schedule remains the same.

Thanks for your consideration on this matter.