I was tethering with my phone for internet access and noticed it was eating my data like crazy. I found that auto-updates were updating my packages and system in the background

This can be turned off via GUI or Terminal

Method 1 - GUI

Open “Software & Updates”

Go to the Updates Tab

Change “Automatically Check for Updates” to: Never

Change “When there are security updates” & “When there are other updates” to: Display Immediately

Method 2 - Terminal

Edit /etc/apt/apt.conf.d/10periodic: Change All of the values to 0 (add comments of original values for switching back if desired)

And you have successfully turned off automatic updates

Remember to turn it back on if you want it when you are hooked up to wifi or ethernet