Is Single Step Conference supported on TSAPI Basic license or will it require Advanced licenses?

SSC consumes one TSAPI Basic license. It does not require a TSAPI Advanced license.

Note that, if you are already using a license to monitor/control the conferenced station, you will not consume an extra license. For example, say you are monitoring S1 & S2. This consumes 2 TSAPI licenses. If S1 is in a call and you SSC S2 into the call, you will not require a third license.

Martin