Those running Insider Preview will be able to upgrade when the OS RTMs
Earlier this month, Microsoft quietly woke up update KB 3035583 from hibernation, and thus began a massive effort to get millions of Windows 7 and 8 users to ditch their existing operating system for a free copy of Windows 10. All they have to do is reserve their Windows 10 upgrade within the first year of the OS’s availability, something they can do from the comforts of their desktop via the Get Windows 10 upgrade prompt.
But what about the 4 million or so people already running Windows 10 in Insider Preview (formerly Technical Preview) form? We know that the finished product, set to arrive on July 29, 2015, will be delivered to them for free as well — a token of gratitude for their help building it. What was unclear was whether they too would need to reserve their free copies?
Someone asked Gabriel Aul, the man in charge of the Windows Insider program, this very question on Twitter the other day, and he had this to say: “You won't need to reserve, and if you're running Insider Preview you'll be upgraded.” And for those of you wondering: Yes, you will need a valid Windows 7/8.x license even if you are part of the pre-release testing program.
From maximumpc
from http://bit.ly/1KRQp6u