I have just downloaded the maps update from the "Hero/LandRover" website onto a USB stick

How long does the physical "in-car" update take and what happens if the ignition is turned off mid-way through?

(I tried to find this on here but can't find any specific posts to the newer sat-nav fitted, I believe, from circa 2016 onwards) MY17 RRS 4.4d V8 Autobiography - Aintree Green (also referred to on Topix as British Racing Green)

OK, so I went ahead, the data was downloaded on to a 64Gb USB 3 stick (100mbs) and had taken around an hour to download from the website.

I plugged the USB stick into the centre consol, followed the instructions and was told it would take about 30 mins. Approx 20 minutes later it was all done.