That section from the instruction is for users who were update to 2.0 because their devices are 2.0-compatible but the migrated from 2.0 back to 1.8 Legacy branch and then decided to move back to 2.0 again.
So, auto-update will happen in case you are running the latest 1.8 Stable 1105 build on your device and it’s a 2.0-compatible device. It’s safe. Remotes on mobile devices (iOS and Android) will have to be downloaded from App Store/Play Market manually in order to be able to connect to the latest 2.0 core.