Seems in the "known networks" you can set the wireless network to a "metered connection" and this stops Win 10 from phoning home whenever you're connected to that network.  It also prevents the spurious reboots when windows wants to install something.

Hope this helps some other folks as well.

Here's how to do it:
http://www.pcworld.com/article/2953132/windows/set-windows-10s-wi-fi-connections-as-metered-to-download-forced-updates-at-your-own-pace.html
 

I had a similar issue, as we have a fleet broadband system on the boat, and when I was connected, Windows tried to download an update.  The only reason I caught it was I saw the link on the switch go nuts.  Had I not shut down the link it would have been really expensive!  I'm really surprised the metered connection setting is not better publicized. 

Not even MS Support knew about it when I called and asked them how I could shut down all the back and forth chatter when I am connected via satellite. 

if you are running windows 10 pro you can also do it with the group policy editor or registry settings.

http://www.windowscentral.com/how-stop-updates-installing-automatically-windows-10

Whichever way you chose you should strongly consider doing it for windows 10 systems.   Just this morning a Microsoft auto push patch cluster corrupted bitlocker's recovery keys rendering the Surfacebook I use for shoreside planning (and work stuff) unbootable.   This will require a complete wipe & reinstall to fix.   I had already disabled update for the onboard systems & left the surfacebook free range as a test.   Now I know.   If they can't even get it right on their own hardware the odds aren't good for everything else.