public function planNextRun()
    {
        if ($this->is_repeating_task && !empty($this->cron_expression)) {
            $this->status = DeferredQueue::STATUS_SCHEDULED;
            $cron = CronExpression::factory($this->cron_expression);
            $this->next_start = date('Y-m-d H:i:s', $cron->getNextRunDate()->getTimestamp());
            return true;
        } else {
            return false;
        }
    }