<?php
declare(strict_types=1);

/**
 * CakePHP(tm) : Rapid Development Framework (https://cakephp.org)
 * Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
 *
 * Licensed under The MIT License
 * For full copyright and license information, please see the LICENSE.txt
 * Redistributions of files must retain the above copyright notice.
 *
 * @copyright     Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
 * @link          https://cakephp.org CakePHP(tm) Project
 * @since         3.2.0
 * @license       https://opensource.org/licenses/mit-license.php MIT License
 */
namespace Cake\Routing\Exception;

use Cake\Core\Exception\Exception;

/**
 * An exception subclass used by the routing layer to indicate
 * that a route has resolved to a redirect.
 *
 * The URL and status code are provided as constructor arguments.
 *
 * ```
 * throw new RedirectException('http://example.com/some/path', 301);
 * ```
 *
 * If you need a more general purpose redirect exception use
 * Cake\Http\Exception\RedirectException instead of this class.
 *
 * @deprecated 4.1.0 Use Cake\Http\Exception\RedirectException instead.
 */
class RedirectException extends Exception
{
    /**
     * @inheritDoc
     */
    protected $_defaultCode = 302;
}

<?php
declare(strict_types=1);

/**
 * CakePHP(tm) : Rapid Development Framework (https://cakephp.org)
 * Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
 *
 * Licensed under The MIT License
 * For full copyright and license information, please see the LICENSE.txt
 * Redistributions of files must retain the above copyright notice.
 *
 * @copyright     Copyright (c) Cake Software Foundation, Inc. (https://cakefoundation.org)
 * @link          https://cakephp.org CakePHP(tm) Project
 * @since         3.2.0
 * @license       https://opensource.org/licenses/mit-license.php MIT License
 */
namespace Cake\Routing\Exception;

use Cake\Core\Exception\Exception;

/**
 * An exception subclass used by the routing layer to indicate
 * that a route has resolved to a redirect.
 *
 * The URL and status code are provided as constructor arguments.
 *
 * ```
 * throw new RedirectException('http://example.com/some/path', 301);
 * ```
 *
 * If you need a more general purpose redirect exception use
 * Cake\Http\Exception\RedirectException instead of this class.
 */
class RedirectException extends Exception
{
    /**
     * @inheritDoc
     */
    protected $_defaultCode = 302;
}

--- 
+++ 
@@ -30,6 +30,8 @@
  *
  * If you need a more general purpose redirect exception use
  * Cake\Http\Exception\RedirectException instead of this class.
+ *
+ * @deprecated 4.1.0 Use Cake\Http\Exception\RedirectException instead.
  */
 class RedirectException extends Exception
 {
Mark routing exception as deprecated.

I don't want to change RedirectRoute or RoutingMiddleware at this time
as I don't want to break compatibility over a small value change.
