Once we post the bits for a pre-release product like we did with the Release Candidate (RC) of Lync Server 2010, the questions start coming pretty quick about the ability to upgrade from that pre-release version to the released version. There is no supported way for customers evaluating the public bits to do this. It is expected that you are running the bits in a lab with the ability to either tear it down or with sufficient connectivity that a new production deployment could have you move the users.
I would say that when we think of labs we think of a deployment that is not able to communicate with the production deployment to avoid schema updates and Active Directory impact of pre-release software.
Agh thats horrible. I had planned on installing Lync and moving my self to it with the though that I would then move to the RTM version when it comes out.