Using map AS, is London-Glasgow via Edinburgh, Aberdeen, Inverness a permitted route?
Map AS is different from the other maps in that it states (in red capital letters): “Only for through journeys from or via London to Scotland.” Route AS is intended to apply to long distance journeys such as London-Glasgow or London-Inverness, and is not designed to cater for deviations within Scotland such as the “via Inverness” that you suggest. If you look up the permitted route from Edinburgh to Glasgow, it is FC, and the map for this shows that the most northerly route permitted is via Larbert. You should take this as also applying on map AS for London-Glasgow journeys, although I realise the ruling on this may not be entirely clear from perusing the Guide. Incidentally, Step 4 (page A3) is not relevant here because, as you correctly point out, London and Glasgow are themselves both routeing points. Qu.2: Does Step 4 rule apply other than for the routeing points associated with the origin and destination? No, it does not. In any case, I am not sure what the purpose would be in det
