As I stated in an earlier post, you really can't turn off Win updates on Win10 in the same manner that you could previous versions of Windows.
If you are connected by wire, you are going to get the updates.
If you only connect wirelessly you can prevent any and all Windows updates if you set your connection type to metered.
When you do again update Windows be sure to check your wifi settings again as the update will likely have reset everything to default values.
So it looks like Windows 10 updates were the culprit. It would make sense, as the latest update was released on Sept 29th, which would correspond with the ten days that this has been going on.
I wonder if it's the mentioned loop problem that has been happening for some people, or that the update may not be able to finish due to not enough data allowance being available. If the update is larger than your daily allowance, it would blow through it, of course, then when you shut down and start again the next day, it may start downloading all over again, especially since a shutdown probably wipes out what has already been downloaded.
At least with it set to a metered connection you can control it.
Edit - Just read a little more and see that HP was trying to download, too. Surely that would just add to the problem of not enough data available. Again, though, I'm glad you got it figured out and were able to adjust the settings accordingly.
wbdavis discovered what the problem was, which turned out to be updates from both Windows and HP.
My advice for you is to download and install Glasswire on your computer (this helped wbdavis, too). It will tell you what is using data on the computer it's installed on. It's free.