shall retain its original availability and shall be treated as a reprogramming of funds under section 505 of this Act and shall not be available for obligation except in compliance with the procedures set forth in that section. The spending plan required by this Act shall be provided by NASA at the theme, program, project and activity level. The spending plan, as well as any subsequent change of an amount established in that spending plan that meets the notification requirements of section 505 of this Act, shall be treated as a reprogramming under section 505 of this Act and shall not be available for obligation or expenditure except in compliance with the procedures set forth in that section. Not more than 40 percent of the amounts made available in this Act for the Gateway