In a Dutch oven, saute' the onions, celery and garlic in butter. Add green onions. Stir in flour until blended; gradually add milk. Bring to a boil; cook and stir for 2 minutes or until thickened. Add the chicken, soup, lemon juice and peel, pepper and salt; heat through. Pour into 2 greased 9x13 inch baking dishes; set aside. In a large bowl, combine biscuit ingredients just until moistened. Turn onto a lightly floured surface; knead 8-10 times. Pat or roll out to 3/4 inch thickness. With a floured 2 1/2 inch biscuit cutter, cut out 30 biscuits. Place over chicken mixture. Bake, uncovered, at 350 degrees F for 35-40 minutes or until golden brown.