This incident has been resolved.

We would like to inform customers experiencing any SSL Certificate issues with Cloud Emails that you will need to update your email settings to "Accept", "OK" or "Trust" the renewed email certificate. The email certificate has been renewed so that you can continue sending all your emails with the appropriate security you need. Once customers have updated this you will be able to continue sending emails as normal. We will provide any further information to assist with this as it becomes available.