I’ve used Fastmail for email since 2015 or so, with a custom domain, and have never had any issues with email delivery to Gmail, Office365, or any other email h

I’ve used Fastmail for email since 2015 or so, with a custom domain, and have never had any issues with email delivery to Gmail, Office365, or any other email host. Data point of one. It’s something I occasionally worry about actually but it has never happened to me. So I probably just shouldn’t worry.