Our upstream SSL certificate provider, Let's Encrypt have provided have provided updates to fix this issue with email apps marking certificates as invalid. We've rolled the fix out and we're now watching to ensure service returns to normal.
As a workaround to the upstream fault at Let's Encrypt, the SSL provider, we’re reissuing SSL certificates with an alternative provider.
Due to the issue impacting thousands of web hosts and millions of users, it’s taking longer than normal.
We're continuing to work with our SSL provider Let's Encrypt for a resolution to the issue.
We'll post further updates as and when they become available.