During The Chimes of Big Ben, and on the steps of the Recreation Hall, Fotheringay asks what his next assignment might be. No.2 tells him that the Colonel will give him his orders when he returns. Fotheringay is also told by No.2 to get back to London before any embarrassing questions are asked. What embarrassing question might they be? And who would ask them?
At the point of The Chimes of Big Ben, it is thought that the village is in Lithuania, 30 miles from the Polish border, well behind the Iron Curtain. If that were the case, then that would make both the Colonel and Fotheringay traitors, possibly defectors, having gone over to the other side! And if that's is the case, then it's no wonder that their non-presence in London might raise some embarrassing questions.
But as it turns out, the village is not behind the Iron Curtain, as it was at that time. So it could be that if the village is not Russian, but a British installation, that another department within British Military Intelligence is behind the village, and one for which both the Colonel and Fotheringay do not work. That might raise embarrassing questions, the Colonel and Fotheringay working for a different department within Millitary Intelligence!
I'll be seeing you