Thanks Lex, Ars Technica is most certainly a reliable source and in this article they are referencing back to the original Inquirer article. Makes sense when you take into account that people have their Windows PC's set to receive automatic updates at a scheduled time, MS will automatically download all the updates prior to installing them. The key here is that the image for Win10 is a very large file that requires a fair bit of bandwidth to acquire, and secondly it is now sitting on the PC of someone who opted out of the upgrade.
MS can easily write this off as "upgrade readiness based upon user settings" but when an individual that purchased a laptop 2 years ago with Win 7 was receiving automatic updates they were never to believe that MS would use Windows Update to change their entire PC.
I always set Windows Update to "Check for Updates but let me choose to download and install them", this way I can sift through the updates and simply hide things like Silverlight, Bing desktop, and ALL Internet Explorer updates, I recommend this setting to all people that have the patience to care for their PC.
In the above case Update KB3035583 would have cancelled the upgrade prompt; https://support.microsoft.com/en-gb/kb/3035583
....but no idea whether it would still download the image file for Win 10.
*As of right now I have a fresh installation of Win 7 SP1 on a desktop for a customer, I will be examining the updates for the appearance of KB3035583 and try to hide it and then restore the hidden update to see how this affect the machine and whether or not it downloads Win 10 even if I remove the update.
Thanks again Lex.