When performing a OTA update with RPA enabled, the dedicated DFU app, nrfconnect app, and nrfutil.exe fail because after the buttonless bootloading has been enabled the device's MAC address changes to the static MAC address of the device + 1 and the applications are unable to handle this situation.
To work around this, the DFU update must be cancelled/time out and then after searching again you can connect to "DfuTarg" and complete the DFU process.
Is it possible to start the nrf bootloader by sending data to the DFU characteristic directly?