This particular one, is in Portadown, a town about 30miles South of Belfast.... I also recently used one at a services in Kenmare, on the Ring of Kerry.... I'm pretty sure I've seen them in Wales and Scotland.... However, my travels thru England recently have mainly only been on the M6, M40, M1, M25 and M20, I'm sure they'll appear, but not sure who the franchise is, or where they're based.... As I've see them in Asda carparks, and also Centra services... So there doesn't seem to be a correlation to any particular outlet.
They are a recent addition, they weren't here a year ago.