“(1) Where an application is made on which a care order might be made with respect to a child, the appropriate local authority must, within such time as the court may direct, prepare a plan (”a care plan”) for the future care of the child.(2) While the application is pending, the authority must keep any care plan prepared by them under review and, if they are of the opinion some change is required, revise the plan, or make a new plan, accordingly.”