12 Supercharger bays included on drawings for a new motorway service area at M6 Junction 1 (Rugby). I posted some details here:
Based on site drawings the development area is northwest of the Junction 1 roundabout and I’d estimate the GPS location of the Tesla bays to be (52.409800, -1.251000). This is currently showing as farmland on Google Maps (I don’t know if any ground work has started yet).
Planning was granted in May 2018 but it’s a big development so may be a while before it’s open - and in the meantime Tesla could switch to V3 superchargers and change the number of bays/site layout I guess.