I have a BMW 3-series and a BMW m'bike and on both of those vehicles I get 'free' map and software updates to the satnav. Says something about Porsche that they charge such extornionate prices for it on their cars.
Indeed, on the car, the UK maps are updated regularly and automatically using the BMW SIM card that is built into the car. So you do not even have to pay the data charges to download the new maps. It all happens automatically in the background.
On the m'bike (which uses a BMW branded Garmin device), I have to download the updates to my laptop and then from there load them into the satnav. But the plus is that I can plot/plan routes/tours on my laptop using Garmin's Basecamp software and then transfer these to the m'bikes satnav device. In the same way, I can put speed camera databases onto the satnav. Oh that I could do that on the device in my Porsche. What Porsche offer is really behind the times and they need to get on the ball