I was surprised to see this as well, however I don't have confidence that this sort of communication will continue.
Iris has always been very inconsistent with communicating with the users. It seems like I saw an email one other time that told about a firmware update. I also recall one user posting that they received a phone call once about a firmware update that was being pushed out which would solve an open issue they had.
Sometimes they used to post here about upcoming updates... and sometimes they didn't, it doesn't appear that they are very active on this forum at all anymore.
They have a "Maintenance and Upgrade" page on the iris website, but to date they have posted about ONE platform update, ONE device firmware update, and one maintenance update for wifi thermostats.
They also have a "release notes" page which received updates (sometimes weeks later) up until version 1.14. Now it has "release notes" for the latest "unreleased" UI update, but doesn't have any notes for versions 1.15 or 1.16 (or any of the minor releases between those).
Any of these avenues for communication would be nice, if they would just stick to them...