LoRa LNS handling of cmd.fifo messages

Basicstation has an interesting feature where messages can be piped into a cmd.fifo file which are then forwarded to the LNS (in this case AWS). I did some experiments with placing the cmd.fifo file and sending it a some sample messages like echo '{"msgtype":"event", "type": "status", "battery": 52, "solar": 123, "temp": 4, "last_full": 4201}' > cmd.fifo

These show up in Basicstation's logs which means I assume they were forwarded to the LNS, but according to these threads, it is the responsibility of the LNS to route these messages. https://github.com/lorabasics/basicstation/issues/46#issuecomment-782753877 https://github.com/TheThingsNetwork/lorawan-stack/issues/3802#issuecomment-782753327

I'd like to be able to send some basic gateway metrics using this method, but it's not clear how they are handled/routed once arrived at AWS.
Is this supported by AWS IoT Wireless?