It's not the only one. I'm aware of at least two others which are not on the road, plus there's this beauty newly finished a complete restoration in Romania. I think it's is due back in the UK later this year.
Zero currently on the road according to the "How Many Left?" website. I'm aware of a few that are currently not licenced including one that's been shipped back to Romania, completely restored, and is now ready to come back to the UK!