FortiClient in standalone mode does not require a license. If there is no EMS license or FortiGate FortiClient Telemetry license, no Fortinet support is provided. A license is required to access Fortinet support.
FortiClient in managed mode requires a license. In managed mode, you apply FortiClient licensing to FortiGate or EMS.
When using the ten free trial licenses for FortiClient in managed mode, support is provided on the Fortinet Technical Discussion Forums. Phone support is not provided when using the free trial licenses. Phone support is provided for paid licenses.