I want to provide an update on the SNI feature request for SmarterMail. We have been in the process of implementing SNI in SmarterMail, along with dynamic certifications from SSL providers like Let's Encrypt or ZeroSSL. However, we ran into a limitation with the .NET Standard Framework that will not allow us to integrate at this time. To fully implement SNI support, it will require a transition to .NET Core.
.NET Core is on our roadmap and will also enable Linux integration for SmarterMail. Now that we've found that SNI requires it, it will urge us to move this up transition even more.
So, we are now reconsidering our plan for the remainder of the year and will share more information shortly. (The joys of constantly changing technologies!)