Adding to @petercooperjr's already excellent observations and suggestions:
- You don't actually need to enter email addresses every time. I should have made that more clear in the instructions. After you enter them once, you've signed up for what Let's Encrypt has to offer, such as expiration notifications, but those are going away soon as @petercooperjr already pointed out.
- There's some discussion going on in this community right now (and I suspect within LE itself) about exactly what the email address submission will do in terms of repeated entry. Given that the plan is as @petercooperjr described where submitted email addresses will no longer be stored in association with an ACME account, I surmise that any addresses submitted could be forwarded to LE's mailing system and possibly added to a set of lists, but I'm not sure at present.
- You can always operate CertSage completely independently of any email address submissions or notifications, so in that regard the email address submissions and notifications are superfluous. For now you can even remove all associated email addresses from your ACME account via submitting an empty list of email addresses, should you so desire. CertSage will continue operating in exactly the same manner.
- I support in the strongest way possible @petercooperjr's suggestion of updating to the latest version of CertSage, which supports certificate autorenewal, provides certificate lifetime information onscreen, and offers more-modern ECDSA private keys in addition to the traditional RSA private keys you are used to getting from CertSage.
- I recently published a lengthy tutorial explaining how to use CertSage with multiple domain names hosted within a single cPanel account, which is linked in its own section on the page for the latest version of CertSage. This could prove useful in checking your setup to determine if you're getting the most out of CertSage.