When you linked the HWID to your MSA using the rs1 (preview) release you can reactivate (if the normal HWID isn't applicable anymore) using the troubleshooter and your MSA.
When I upgraded My 10586 Home copy to 14388 Pro, I used the Activation Troubleshooter and it didn't even ask for My M$ account
Thanks guys. Got what you were saying, but the link from KNARZ really cleared it up. So if I were going to start upgrading my computers to 10 this weekend, how should I go about doing it. I'm planning to use the gatherosstate and fresh install from a USB. Should I use the 14388 (or 14390) esd to build and ISO and bootable drive, or use the Windows MCT and get the update when it's officially pushed out? I ask because I'm currently in process of using the MCT to download an ISO and would rather stop it now and go the other route if it's suggested. I haven't looked much yet, but any guides you can link me to for converting the ESD into an ISO?