The Local Government Area Changes Regulations 1976

10.  Any form supplied by any of the bodies specified in paragraph 8 in the exercise, by such body, of a function which by virtue of any directions given under section 7 of the National Health Service Reorganisation Act 1973 or of any other provision of that Act is a function exercisable by an area health authority or a family practitioner committee shall continue to be a valid form in connection with the exercise of any function until it is cancelled or withdrawn by the Secretary of State or by the body exercising the function in place of the body by which the form was supplied, and as if any reference contained, in such a form to a body by which the function was exercisable before the appointed day was a reference to the body exercising that function on and after that day.