Believe this is what you are looking for:
First, the Slow-approved patch goes out to all consumer Windows 10 customers -- the ones with "free" Windows. Consumers have no choice about it; they will get the patch, thereby being updated to the "Current branch." Presumably Windows 10 will have some mechanism for prohibiting reboots at specific times of the day, but that's the extent of individual customers' control. There will be no ability to shut off automatic updates (short of permanently disconnecting from the Internet), no provision for blocking specific updates, and no way to roll back updates -- either one at a time, or en masse -- should they cause problems. I haven't seen any official announcement that lays the process out quite so starkly, but that seems to be where we're headed.
How Windows 10 updating will work: The devil's in the details | InfoWorld