ADOM version 7.2 supports policy package installation to the lower version of FortiGate on FortiOS 7.0. 7.2.1

ADOM version 7.2 supports policy package installation to the lower version of FortiGate on FortiOS 7.0. During the installation process the CLI 7.2 syntax is automatically converted to 7.0. syntax to match the OS version.

• FortiManager 7.0 ADOMs can concurrently manage mixed FortiGate devices running FortiOS 7.0 and 7.2.
  
• Navigate to System Settings > All ADOMs > More, and select Upgrade to upgrade your 7.0 ADOM to 7.2. After the ADOM is upgraded to 7.2, the new GUI features are automatically displayed.
  
  
• In the upgraded 7.2 ADOM, create a new firewall policy and then install the policy to FortiGate units running 7.0 and 7.2. FortiManager will automatically downgrade the 7.2 CLI syntax to 7.0 syntax when the package is installed on devices running FortiOS 7.0. The full policy package will be installed to devices running FortiOS 7.2.