I noticed after a few days into the cycle my internet slowed down. There wasnt anything obvious to find where it was going. i have a pw on my router and its a hard one to figure out. noone was piggybacking and its only my computer and wifes phone. cannot for the life of me where it went.
My neighbor, who just got internet had the same thing happen. He didn't listen when I told him to change his Windows update settings. Both of his computers upgraded to Windows 10, then proceeded to update themselves, then sent all of those updates out to other users over the internet.
He thought he had 30 GB so, he updated his cell phones and got a few apps on them too. Used 174 GB overnight. Oops.
Yes that's what Windows 10 will do if you don't change some settings. 1. Set to metered connection - that stops downloads of updates. 2. Set updates to only be shared with your LAN - that stops Windows form uploading updates to the internet but, still lets all computers on your home network update from the one download you manually allow.