There’s a certbot addon which uses nginx directly to renew the certificate (so you don’t need to stop the web server to renew). If you install the addon you just use the same certbot commands but with --nginx instead and it will perform the actions without interfering with web server operation.
You just then make sure the cron job to renew also includes --nginx and you’re done.
I have auto redirect to 443. But --nginx works fine. I think it overrides stuff for whatever the specific url used is.