13The coming into force of any provision of Part IV of this Act which re-enacts a provision of Part IX of the [1984 c. 60.] Police and Criminal Evidence Act 1984 (police complaints), as amended by the [1994 c. 29.] Police and Magistrates' Courts Act 1994, shall not affect any procedures established by virtue of section 96 of the 1984 Act (constabularies maintained by authorities other than police authorities) before that provision comes into force.