I've a quick (and silly question) for staging certificate.
I use LE in a CI environment, so quite often I use staging certificates.
When it comes to reach the Expiring date, I got email from LE for these certificates.
So, I wonder if:
Avoid to get notification for staging certificate at all
Or put a fake email for staging cert, so the email cannot be received.
Providing an email address for the Let's Encrypt staging environment is optional.
Your ACME client might have an option to omit an email address when registering. With Certbot, you'd provide --register-unsafely-without-email instead of -m/--email.
You can also update your ACME account to remove any or all of its email address.