Glamorgan tetrad update

I know it's been less than a month since the last one, but a little clarification is needed within NPT. Although the west is getting closer to achieving the nominal target, many squares still have lots more to offer and will benefit from revisits. As always, flick between the two to see the changes from the previous updates (PS. I'll update this map with Sam, George & Peter's additions when they come through from Dave).