RAK4260 TTN connection

I’m trying to follow your instructions for connecting a RAK4260 to TTN, I have cloned your demo code from github, I have updated conf_app.h with my Device’s EUI, my TTN Application EUI and the appropriate AppKey, I have compiled the code and programmed the module successfully. The code runs and communicates as expected at 115Kbaud. It successfully joins the network and returns a Device Addr,
it also claims to successfully send temperature data and indeed I can see packets are being forwarded by my gateway. HOWEVER it does NOT join or communicate with my TTN application, the data is going somewhere else because I see no activity for the device at all on my TTN console.
FYI I have tried setting SUBBAND to both 1 and 2 without success.
Is there anything else I need to change in the source code?
Are there any further details I can supply?
Thanks for your attention,

I made some progress…
FYI it seems necessary to run the “Clear PDS” option from the “Main Menu” in order for any changes to conf_app.h’s DevEUI, AppEUI or AppKey to take effect. This non-obvious step is not mentioned anywhere in RAK’s documentation, hope this will save someone some time down the line.