We would like to leverage the MQTT networking libraries from the BG96 and thus looking at removing the MQTT libraries.
But we only have the MQTT dependencies (https://docs.aws.amazon.com/freertos/latest/userguide/freertos-mqtt-2.html), is there any way to find out what libraries depends on the MQTT so that we can assess the impact should we abstract the MQTT functions to use BG96 MQTT library?
Richard, hello, small world 
FreeRTOS libraries that use MQTT include Defender, Fleet Provisioning, Greengrass Discovery, OTA, and Shadow. Are you finding that the MQTT interface provided with your BG96 hardware is dramatically different from the MQTT interface provided by FreeRTOS?
Also, if you don’t mind, did you explore the possibility of porting the FreeRTOS MQTT library to the cellular transport interface? That’s admittedly a shot in the dark (and counter-productive if MQTT is offloaded to your radio), but I’m wondering if you ran into any other challenges. We’d value the feedback. Thank you.
Hey Dan, great seeing you here too! Sorry for slow response on this.
Main reason of exploring the options, was that we are thinking of reducing the firmware footprint and not having to maintain the extra library, since there is some overlap between the FreeRTOS MQTT and the BG96 MQTT.
However, indeed as you pointed out, we found some dependencies between the other critical functionalities especially the OTA to the MQTT library, thus for now we will use the FreeRTOS MQTT instead of the MQTT API from the BG96, and probably revisit this later, and will definitely update this thread for any findings we have!
Thanks again Dan!