Apparently the MoD have been doing some contingency planning, and sent some top brass over to check out the lie of the land:
Based on the information [Senior British military officers] collected, they are devising an evacuation plan for some 8,000 British civilians in South Korea (Chosun Ilbo).
I suppose it was the responsible thing to do after the RUSI report, Preparing for War in Korea, published last September. If I recall right, when the British Korean Society arranged for our ambassadors in Korea to give a talk last Spring, the one question which friends in Korea wanted me to ask was: What are the evacuation plans in the event of war? (The Americans seemed to be so much more prepared for such an eventuality). So maybe an answer to the question is getting closer.