Block WordPress Post Updates and Deletion After a Set Period. ganked from here as may need this in future.... http://www.wpbeginner.com/wp-tutorials/how-to-block-wordpress-post-updates-and-deletion-after-a-set-period/

wp-block-updates-after-time.php

function wpbeginner_restrict_editing( $allcaps, $cap, $args ) {

    // Bail out if we're not asking to edit or delete a post ...
    if( 'edit_post' != $args[0] && 'delete_post' != $args[0]
      // ... or user is admin
      || !empty( $allcaps['manage_options'] )
      // ... or user already cannot edit the post
      || empty( $allcaps['edit_posts'] ) )
        return $allcaps;

    // Load the post data:
    $post = get_post( $args[2] );

    // Bail out if the post isn't published:
    if( 'publish' != $post->post_status )
        return $allcaps;

    //if post is older than 30 days. Change it to meet your needs
    if( strtotime( $post->post_date ) < strtotime( '-30 day' ) ) {
        //Then disallow editing.
        $allcaps[$cap[0]] = FALSE;
    }
    return $allcaps;
}
add_filter( 'user_has_cap', 'wpbeginner_restrict_editing', 10, 3 );