@jcaron Just to clarify something from our use case: In our experience using the same frame counter is not a problem with our private instance of a TTN server. How we do it now is that we restore from nvram and save it immediately after. This is so we don't need to think about it again. I understand ADR will not work for us here, but it is still a lot easier and spares us from some logic with exception handling and still keeping the session and avoiding a new join. We also do not need to receive responses. We are basically using it as a makeshift abp connection, as our setup and back-end does not support abp. Having a function that restores the session without erasing it would actually be quite nice for our case. This, as far as I understand it from TTN, does also work for the public TTN network, but I have not confirmed this. Is there some way of getting all connection details down in a file so we could save it to an SD card instead? This would actually allow us to quite efficiently create devises and manage the things for our system.