It's already out for some people but not for all yet and it's been confirmed by a lot of Reddit users that this is not region specific.
You'll find a folder in you C:/ drive called "$Windows.~BT", which is basicall where Windows 10 is being downloaded and the final size should be over 6GB (mine is still at 140MB
). After the download is complete you will be notified via a pop-up window to install it