Preheat the oven to 400 degrees and line a half-sheet pan or cookie sheet with parchment paper. Add flour, ¼ cup sugar, baking soda and salt to the bowl of a food processor. Pulse a few times to combine. Add the butter cubes to the flour mixture and pulse until small and medium sized crumbs form. Add 1 1/3 cups sour cream and vanilla. Pulse until it is just combined. Turn the dough out onto a floured board and knead just to combine everything (do not overmix). Press the dough out with your hands to about 1-inch thickness and cut using a round biscuit cutter. Place the biscuits on the parchment paper lined sheet and refrigerate for 20-25 minutes. Just before baking, brush the tops of the biscuits with the egg wash and sprinkle with the Turbinado sugar. Bake for 16-19 minutes or until golden brown. Remove from the oven and allow to cool completely. Add the heavy cream and ½ cup sour cream to a cold mixing bowl. Mix on high speed until soft peaks begin to form. Add the confectioner’s sugar and vanilla to the cream and mix until stiff peaks form. Set aside or store in the refrigerator until the shortcakes are ready to serve. Meanwhile, add the strawberries and blueberries to a medium sized bowl. Sprinkle with the remaining ¼ sugar. Pour the orange juice over the berries and toss together. Allow the berries to sit for 15-20 minutes or until the juices develops. Cut the completely cooled biscuits in half horizontally. Add the berries to the bottoms of each biscuit and top with whipped cream. Add biscuit tops and then add a few berries and whipped cream to the top of the biscuit and serve.