Happily, I realized my mistake immediately and was able to fish out the extra baking soda.
From that point on, I paid close attention to what I was doing! Mixing the butter into the flour with my fingers is a delightfully tactile experience. I took Dorie's "playing around" advice and mixed in some diced banana for an extra bit of pizzazz. I took the scones to my weekly brunch where they were much enjoyed.
Thanks to Patricia from Life with a Whisk for choosing these wonderful scones. And next week it's my turn to choose--can't wait to make Caramel Pots de Creme.