I saw that Salesforce.com certificates are changing from being issued by Symantec to being issued by DigiCert. I'm concerned this will affect Heroku Connect.
Heroku Connect uses Mozilla's certificate bundle as provided by python-certifi. The new DigiCert root, as linked to from Salesforce's Knowledge Base article, is actually present in our certificate bundle. When Salesforce transitions to these new certificates, communication between Heroku Connect and Salesforce should not be interrupted.