Preheat oven to 400-degrees. Combine yeast and warm water in a small bowl: let stand 5 minutes.In a large bowl whisk together flour, sugar, baking powder and baking soda. Cut cream cheese and butter into the flour mixture with a pastry blender until crumbly.Combine yeast mixture and buttermilk, then add to flour mixture, stirring just until the dry ingredients are combined. Turn dough out onto a floured surface and knead for about 2 minutes.Roll dough out 1 inch thickness. cut with 3-inch cutter for small biscuits or use a larger cutter for larger biscuits. Continue to reshape and roll dough.Place biscuits on a sheet pan lined with parchment paper or a silicone mat.Bake at 400degrees for 15 minutes or until lightly golden.Brush with melted butter.