CheckMK 2 Backwards Compatible with 1.6 Agents?

I know the guide you’ve provided states this already, more making sure in your experience what the best practice would be.

Also, when I was reading the update process I couldn’t find in 1.6.0p9 how to disable the agents in this version (pictures look like they reflect 2.0). Any suggestions to disable all the agents from checking in while the update happens?