I was trying to plan a trip close to the RA(T) for the Farnborough Airshow and found that NOTAM J1311/12 (AIC Mauve 059/012 also refers) is not being drawn correctly on SD Plan. It appears to be drawn as a simple circle centered on Farnborough.
Perhaps Tim would like to comment

No doubt the SD team has more detail, but it's worth remembering that any graphical NOTAM software can only accurately display the "area of influence" which is is coded in the Q-line of the NOTAM (i.e., whatever the author of the NOTAM thought was the area where the NOTAM is of relevance; by definition it can only be a circle). The actual area definitions within the long text of a NOTAM are not really fully standardised. and while most software makes a reasonable guess for simple areas, something as complex as the FB airshow restrictions are usually beyond its capabilities.

IMHO, given that parts of the RA(T) change by time on the day, and also for some days interact with the Olympics restrictions, I wouldn't trust any such software's guesstimate and rather go with the actual change maps that the CAA, FB and others have issued.