Preview feature management is also known as beta feature management and has the following salient characteristics:

• If you've been invited to try an LCS preview, you can enter a code or enable the preview here.
• Public previews are available for any LCS user.
• Private previews are only available to users and organizations that have been invited to participate.
• To get involved in LCS previews, you need to sign up for the Microsoft D365FO feedback programs.

Now, let's look at the usage profile/subscription estimator, which is important for sizing your environment.