Not sure about the UK version, but the link above from slyugo works for USA and Canada. On their website they have a way to report errors etc (which I had to use because it kept telling me I had selected Canada as my region even though my vehicle was from USA: It was an error they were aware of but it didn't prevent me from getting the software).
Anyway, you might be able to go on there and ask where you would get the UK version. There might be a nominal fee (it was only about $30 including shipping for me and I can confirm that it does in fact include Android Auto (and I assume Apple Carplay as well).
Hope this helps. By the way the update process is super easy (directions included in the package and there are YouTube videos too), but takes about 30 minutes or so: With the power off, replace the SD card you have in your system (there's a slot just above the AVN screen) and then power on the system. It will check it and so on for a few minutes and then boot normally. Then go into settings and go down to "System Info" and then "Update System". Sit back and wait for it to complete. The screen might go totally blank for long periods of time but don't panic! It will eventually finish and you'll be good to go. When it's finished leave the SD card in the slot.