Lemon Poppyseed Muffins

2 cups all purpose flour 1 tsp baking powder 1/2 tsp kosher salt 1/4 tsp baking soda 1/2 cup Sour Cream 1/2 cup buttermilk 2 Tbsp fresh lemon juice 1 cup granulated sugar 1/2 cup (1 stick) unsalted butter, room temperature 1 Tbsp grated lemon zest 2 large eggs 2 tsp poppy seeds