As a follow up to my post on Let's Encrypt Certs on Heroku, here is how you update your certs when it's three months in and they are expiring.
$ sudo certbot certonly --manual -d www.giftionary.city -d giftionary.city
Host the files it tells you to, then run:
$ sudo heroku certs:update /etc/letsencrypt/live/giftionary.city/fullchain.pem /etc/letsencrypt/live/giftionary.city/privkey.pem Resolving trust chain... done ▸ Potentially Destructive Action ▸ This command will change the certificate of endpoint maiasaura-85929 from ⬢ giftionary. ▸ To proceed, type giftionary or re-run this command with --confirm giftionary > giftionary Updating SSL certificate maiasaura-85929 for ⬢ giftionary... done Updated certificate details: Common Name(s): www.giftionary.city giftionary.city Expires At: 2017-03-26 15:45 UTC Issuer: /C=US/O=Let's Encrypt/CN=Let's Encrypt Authority X3 Starts At: 2016-12-26 15:45 UTC Subject: /CN=www.giftionary.city SSL certificate is verified by a root authority.
And then you're done!