private function cleanupAppServers()
    {
        $allFoundServers = $this->loadAppServerList();
        /** @var \OxidEsales\Eshop\Core\DataObject\ApplicationServer $server */
        foreach ($allFoundServers as $server) {
            if ($server->needToDelete($this->currentTime)) {
                $this->deleteAppServerById($server->getId());
            }
        }
    }