Hello,
I came across your brief which is rather fortunate as there are not many practicing LoRa and LoRaWAN specialists here. I work with LoRa and LoRaWAN daily, also have my own private network and are both LoRa Academy and TheThings certified. I build my own concentrators with RAK2287 and custom OS images and basicstation protocol and use a significant amount of RAK wireless modules for sensors and the like.
Feel free to contact me at your convenience and we will take a look at how to address your concerns, particularly your OTAA configuration.
Warmest Regards,
Stephen Lombard
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