Hi, thank you for the suggestions; I'm doing some tests.
I found the ArduinoIoTPreferredConnection.getClient() instruction, and it's possible to pass it to BearSSLClient.
I've tried both the code you suggested and ArduinoIoTPreferredConnection.getClient(), but when I execute myBot.begin(), I receive the response "Unable to connect to Telegram server," and the connection with the Arduino cloud also drops: ArduinoIoTCloudTCP::handle_Disconnect MQTT client connection lost and Board disconnected from Arduino IoT Cloud.