Heat oven to 350. Butter and flour a 12 inch Bundt pan. In a large bowl, whisk together flour, baking powder, baking soda and salt. Set aside. In another large bowl, beat butter until smooth. Add sugar and beat for 2 to 3 minutes until fluffy. Add eggs, one at a time, and beat well after each addition. Add sour cream, lemon juice, lemon zest and vanilla and beat until combined. Beat in flour in 3 additions, alternating with the buttermilk. Beat for 2 minutes on medium-high. Fold in blueberries. Spoon into prepared pan. Bake at 350 for 50 – 60 minutes or until a toothpick inserted in the center of the cake comes out clean. Cool on a wire rack for 20 minutes. Run a sharp knife around the edges of the pan. Turn out and cool completely. For the glaze, in a small bowl, mix together confectioner’s sugar, lemon juice, limoncello and syrup until smooth. Drizzle over the top of the cake and let it roll down the sides.