Lets Encrypt contact details cannot be updated
Once the client has been registered, changing contact email doesn't update the server registration.
This isn't great for when we have auto-enabled lets encrypt for you. You can't go in and add your contact information.
Updating your registration email is supported by LE: https://ietf-wg-acme.github.io/acme/draft-ietf-acme-acme.html#rfc.section.7.3.2
But it is not available in the acme-client gem: https://github.com/unixcharles/acme-client/issues/81