Does anyone know if these units support data tethering via Bluetooth so that I can give the stereo internet access via my mobile phone without having to use a WiFi hotspot?

ONly just got my Qashqai so not sure if it's the same but I had a similar problem with a Porsche Panamera. Porsche wanted me to buy the whole unit but in the end it turns out there was a control unit attached tothe DRL, changed that and all OK. Hope this helps.