Civil Servants have to be one hundred percent behind the Government of the day and impliment their policies. So at the time of a General Election they could go from a left wing government, to a right wing one. Their allegiances would have to switch completely and literally overnight, irrespective of any personal belief.
Cobb, at the end of 'Arrival' he's dressed for the city, a Civil Servant. And it is my belief that during Cobb's stay in the Village that there has been a General Election in Great Britain, and when Cobb makes the remark that he mustn't keep his new masters waiting, he was not refering to any defection, but working as a Civil Servant he was refering to a new government for which he would have to work.
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