I’m switching the status to Partially Done.
The request for a Preview Team is still in the works. No new information is available at this time.
Team Discoverability is still being worked upon, no details are available at this time. If you support this idea please navigate over to the main topic and vote for it! https://microsoftteams.uservoice.com/forums/555103/
Change Prompt: this has been completed
The feature team is still reviewing, there is lots of discussion about this item and I hope to have a decision soon.
We acknowledge the customer demand for Private Channels and have been hard at work on it. Private Channels is currently in preview with a select group of customers. We expect to release the feature to the public later this Fall, and will update here when we are starting to roll out to all customers. We appreciate all the feedback you have provided to us on this forum and thank you for your patience.