Satellite radio question

[Tundralag]

So was listening to the sat radio today on my way to the base, had to stop at the red light under the overpass. Of course I lost sat signal but as soon as I did a prompt came up asking if I want to stream over the internet. Of course I hit yes and the music continued.

Now my question how does that work and just what stream are they using since I don’t have a phone hot spot setup. Is this some free package that comes with the 12 inch screen???