"I'm also working on the 2010/2013 migration now. I was planning on installing and configuring E2013 on new servers, setting up policies, testing backup etc. before activating the new load balancer rules/coexistence. I'm assuming no clients will be able to connect to E2013 until the load balancers can. Bad things happen when I assume though. This should work right?" - Wes Hoogenboom