Using ARD to do mass upgrades? I am trying to find a method of Upgrading many computers, for example to 10.10.x to 10.12.x . Is there a way of doing so using Apple Remote Desktop? Planning to update about 40 computers. 

I am able to update from 10.12.4 to 10.12.5 but so far I have not made much progress with an upgrade. Would AutoDMG be a step forward without deleting the files already on the computers?
You can use Apple Remote Desktop to copy the macOS Installer application to the Applications folder on every client Mac, then send the following UNIX command as root:

/Applications/Install\ macOS\ High\ Sierra.app/Contents/Resources/startosinstall --applicationpath /Applications/Install\ macOS\ High\ Sierra.app --agreetolicense --nointeraction


This command starts the in-place upgrade action to macOS High Sierra. It may take some time for the entire process to complete, but it doesn't require any user interaction.