I do understand. Your cc desktop app shows any available updates to software. If you had any CC 2017 app installed the desktop app will show updates available and remove and upgrade to 2018.
The same happens with acrobat. It’s not identifying your current load as DC, it’s telling your users an upgrade to DC is available. When they click it - it will upgrade to DC.
Teams is managed different from enterprise. Your only two options is to remove the user upgrade option or tell them to ignore it. Your IT dept should be able to easily manage and push out updates to users using the Teams packages you create.