I hope you get an answer to your email. You said your block measures 10 1/2 x 10 3/4. Which measurement is the LENGTH of the block and which is the WIDTH? If the WIDTH is the longer measurement, you need to adjust your seam allowance just a bit (make it slightly fatter) If the LENGTH of the block is the longer measurement, trim each strip to the exact length you need before sewing them together and remember that any diagonal seam can stretch a tiny bit. Ironing instead of pressing can also cause some stretching. If you are using WOF strips, they can also stretch a wee bit with handling--more than LOF strips.
In all honesty, I would not worry about 1/4 inch over a 10 inch length. Just put the longer piece on the bottom when sewing two blocks together, and let your feed dogs do their job.