Jane, do you mean blocks that are 8 1/4" in one direction (or two)? Or the "matching" of the seams that create the design are off 1/4"? Or either/both? If the block is at least 8 1/4" square I can make it work, but this should be the max variation on block size, in my opinion (of course we should all strive to be 8 1/2" and hopefully the 8 1/4" blocks are few...like you I try to do my own QC before sending and set aside any with significant variations from specifications). Minor variations in matching seams happen to all of us, but if the match is off 1/4" it will be really noticeable. Just my two cents.