Section 22. After an appeal has been claimed and filed in the registry of probate, all proceedings in pursuance of the act appealed from shall, except as otherwise expressly provided, be stayed until the determination thereof by the supreme judicial court or appeals court; but if, upon such appeal, such act is affirmed, it shall thereafter be of full force and validity. An appeal from an interlocutory order, judgment or decree, however, shall not suspend proceedings under the same pending the appeal, except as otherwise expressly provided by law.