Nope. There is no option to turn it off completely in the GUI. Windows 10 ALWAYS warns you it's going to reboot for an update with an option to postpone.What you don't get is an option to delay the patch/update in the first place. So once Windows has decided to "upgrade" you're forced to go through the let's-reboot-3-times reboot when you next shutdown.
In my case it was "worse" (it didn't really matter to me, but it could have done so).
Last night I asked my laptop to look for updates. It reported it had found none. I then looked at the Microsoft blog page about how to force an update (happy for my laptop to go first...) and suddenly the update page (open next to my browser) decided it had two updates - an Adobe Flash one (again) and Windows 1709.
That was the better part of 3 hours (and that's on a system with an SSD).
So it downloaded them and installed them. Except the 1709 download failed to install, so it downloaded it all again. This time it installed OK and I was left with a Restart option. Whcih I selected and 3 reboots later I had Windows 1709. I then had to go in a patch the registry to switch off auto-login on accounts with no password (which MS always decides to reset for me...how kind) and remove the login page image.