SamMobile reports that the Galaxy Beta Program is almost set for a re-launch to tune Android 8.0 for the spring models. Specifically, the US FAQ points to Galaxy S8 and Galaxy S8+ for Sprint, T-Mobile or unlocked versions.
Those who have those device variants and would like to participate in the program can get ready to do so by downloading the Samsung Members app and registering. Invitations have not gone out as of yet, but you’ll be in position to get in when the program is announced.
You can see the End User License Agreement here.