does not respond with 503 status code

Hello,
Plugin is working great for me now, with no problems at all. But one thing cought my eye. In maintenance mode, the site does not respond with 503-Service Unavailable code, but instead probably the normal 200 code. How does the plugin handle the maintenance mode?
I will have to activate maintenance mode every evening, deactivating in the morning, due to the operation of the website. Do you think it not responding with 503 will cause a problem? I’m asking especially about the search bots. Can anyone suggest a better way?
Thanks for any information,

Deniz

https://ww.wp.xz.cn/plugins/responsive-admin-maintenance-pro/