Dual telemetry issue

Hello everyone,

We are going to use LTE modem and RF modem to maintain a stable communication environment with FCC. That is, the use of dual telemetry.
I tested the connection with two RF modem, but I have one question.

hardware environment

RF modem 1 <—> FCC <—> RF modem 2

RF modem 1 <—> Laptop(QGC) <—> RF modem 2

When i connect to Laptop(QGC), i can see that telem1 and telem2 are connected. But, telem1/telem2 selection is not possible.
I want to change telemetry number, if it is possible.

For example, LTE modem operates in long-distance flight situations, and QGC operator selects RF modem instead of LTE modem in short-haul flight.

Does anyone know about that?