I'm afraid I have to disagree rearding the availability of disks - my (MY2014) XKR came with a 2013-2014 DVD installed (see photo attached) which I subsequently replaced with a 2019 disk (looks exactly the same other than the dates) - this is the last 'official' disk for the car and is available from various sources including ebay for £20-25.
There are stories of newer versions (I believe utilising Volvo maps) but as N6 has stated, be very wary of them as they may well do more harm than good....