What are SerialNina and SerialHCI supposed to be used for? (Arduino Nano RP2040 Connect)

Essentially, I'm trying to figure out how I can use Bluetooth Classic using the on-board U-blox w102 Wifi/Bluetooth module. I'm assuming that SerialNina and SerialHCI are somehow connected to it and maybe the way to use Bluetooth Classic on the Nano RP2040.

The ArduinoBLE library uses SerialHCI in HCIUartTransport.cpp. It also messes with NINA_RESETN and SPIWIFI_SS a bit in BLELocalDevice.cpp, but I'm not too worried about those.

The WiFiNINA library uses SerialNina to update the wifi firmware in SerialNINAPassthrough.ino and ESP32BootROM.cpp.

From this, I'm assuming that SerialHCI can be used to control BLE and SerialNina updates the Wifi's firmware. Am I right about this? If so, what part of the Nina-w102 module is SerialHCI connected to?