Route::filter('stylesheetFilter', function($route, $request, $response, $value = null))
{
    $response->header('Content-Type', 'text/css');
}

Route::get('/assets/{theme}/style.css', array('as' => 'stylesheet', 'after' => 'stylesheetFilter' function($theme)
{
    return View::make('custom_styles')->with('store', $theme);
}));

source: http://laravel.com/docs/routing#route-filters

You can try to put Session::reflash() in style route closure. It should take old flash data and set is a current one so it should be available in next request.

Yu, what @maksymcierzniak said - use Session::reflash() anywhere where you don't want the request to consume the session flash data.