Tosh - good question! I suspect all their knees are joined together, as they all jerked at once at first mention of the 'x' word. Political Correctness usually goes hand in hand with naivety - they mean well, but will only understand the big picture as they grow older!
ArkRoyal - Agree fully. My Gujarati evening classes start next week.
BB - Got them going nicely! Ref your actual question, I'm not sure that non UK Passport holders should actually have to leave our shores. It would probably be legally difficult to remove someone from a job once they're contracted for a given time. The onus will be on UK employers when recruiting starts again. Of course, you can bet your life the dreaded 'R' word will then appear!