Thanks again, all, for the input. I like the idea of not amending the non-refund years, but I'm afraid I am just like Tom and want a perfect paper trail from point A to points B,C,D,E, and F if I am ever called upon to justify it. On a more practical note, it is easier to bill the client for an amended return than it is to bill for hours of account9ing time in creating a spreadsheet that leads to the amended return.