In a 1 cup glass measuring cup, combine yeast and warm water. Let stand 5 minutes.
In a large bowl, whisk together flour, sugar, baking powder, baking soda, and salt.
Cut in butter and shortening with a pastry blender until crumbly.
Combine yeast mixture with buttermilk and pour into flour mixture. Add blueberries. Stir just until dry ingredients are moistened.
Turn dough onto a lightly floured surface and knead gently just until dough holds together and is even in consistency.
Roll dough to 1/2-inch thickness. Cut with a 2 1/2-inch biscuit cutter. Place biscuits on 2 ungreased baking sheets.
Bake 12 to 15 minutes or until golden.
Place cream cheese in the bowl of an electric mixer and beat for 10 seconds. Turn speed to low and gradually add confectioners' sugar. Beat in vanilla and gradually add milk until desired consistency is reached.