Here is a previous discussion on Mantria
http://www.city-data.com/forum/tenne...middle-tn.html
I own land near three of their places (Indian Trail Phase II & III and Iron Bridge).
I haven't see much happen there in the last couple of years. However, they have been doing some work on Indian Trail Phase II in the last month.
Interestingly, I saw their schedule today on their website.
Mantria Communities -> Communities
According to it, Iron Bridge should have roads by July 1st. I will be up there this weekend. I will be surprised if there are roads.