#13: author_rewrite_rules

author_rewrite_rules.php

<?php
/**
 * Change 'author' permalinks to 'contributors'
 *
 * @see WP_Rewrite::rewrite_rules()
 *
 * @param array $author_rewrite The authors rewrite rules.
 *
 * @return array The filter rewrites array.
 */
function wpdocs_contributors_rewrites( $author_rewrite ) {
	$contributors = array(
		'contributor/([^/]+)/feed/(feed|rdf|rss|rss2|atom)/?$' => 'index.php?author_name=$matches[1]&feed=$matches[2]',
		'contributor/([^/]+)/(feed|rdf|rss|rss2|atom)/?$'      => 'index.php?author_name=$matches[1]&feed=$matches[2]',
		'contributor/([^/]+)/page/?([0-9]{1,})/?$'             => 'index.php?author_name=$matches[1]&paged=$matches[2]',
		'contributor/([^/]+)/?$'                               => 'index.php?author_name=$matches[1]'
	);

	$old = array();
	// This relies on you registering a 'redirect' query var and handler.
	// The handler would check for 'redirect' and apply a wp_redirect call where necessary.
	foreach ( $author_rewrite as $endpoint => $query )
		$old[$endpoint] = $query . '&redirect=1';

	return array_merge( $old, $contributors );
}
add_filter( 'author_rewrite_rules', 'wpdocs_contributors_rewrites' );

http://fotd.werdswords.com/author_rewrite_rules/