Microsoft invited Office Insider program members to test the “One Outlook” client 10 months ago. The latest news says that the application will open in April this year to invite more users to test.

In the Microsoft 365 roadmap page, the entry information shows that Microsoft will invite Microsoft 365 subscribers of Current Channel to test the new version of “Outlook for Windows” preview in April this year.

Michael Reinders also shared a note from Microsoft in the tweet, saying that Microsoft will introduce a new version of the toggle button to open a new experience for all Current Channel channel users in late April.

The note mentions that Microsoft 365 customers will not be forced to switch to the new Outlook at this stage, and personal Microsoft accounts as well as Microsoft Exchange Online accounts will be able to try it out.
The new One Outlook for Windows will allow better integration with Microsoft Teams, as well as improve its calendar features, the way Outlook automatically pins important emails to the top, and more. Eventually, this application will completely replace the current Outlook application.