* by working, I mean is passed 'fit to run on Network Rail infrastructure' and with all systems basically working but may contain faults or need software updates or certain parts, I don't mean necessarily 'passed fit for passenger service'.
I'm conscious of the fact that whenever a new kind of train does a promotional run (for the press, and stakeholders) the unit used is invariably an example which hasn't up to that time appeared in public service, and which doesn't do so immediately thereafter.
There is presumably a fine line between being 'passed fit for passenger service' and being 'passed fit to carry the general public'.