In message , Andrew Clark
writes
That would have been done long before, when the lines were shut to the
public.

You see, I think you have in mind some sort of orderly gradual
transition from normality to emergency, when the government announces a
problem and TfL responds by ordering all the LT staff to clear the
system of rolling stock, and generally closes it all down neatly.

A good example of this was 7/7. Trains were abandoned all over the
network. It was a day or two before they'd all been rounded up and put
in their respective depots.
--
Steve Fitzgerald has now left the building.
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