Thanks for the comments. I don't think it's quite like any other VPN service, at least not that I'm aware of. Fortressa provisions a distinct server, with its own OS, and sets it up as a VPN for you -- and only you.

I anticipated questions like those you raised and tried to answer them ahead of time in the FAQ, which admittedly isn't very easy to find at the moment. Having a look at it, does it help answer some of the questions you asked? https://fortressa.com/faq/