Oh, I think I misread the question. If it's only an issue of mixing up the order of pieces in the block, I subscribe to the motto "one block that's different is a mistake, two or more blocks that are different are a design." I would just repeat the change elsewhere in the quilt top & call it a day. It's nice to change things up once in a while & sometimes goofs are the best/only way to find a new way to do something. I love things that are different from the "norm" and would go with it & figure it was just meant to be that way now.