In this day and age, if the tooling and fixtures are set up correctly, with the right programs the work doesn’t need to stop when the lights go out. Of course you may get some failure and crashes, but those happen anyway.
And this shop can probably machine just about anything, in any quantities from single prototypes to thousands. This doesn’t mean that old style machining is going away. It’s not. Many jobs, if the expectation is that you won’t be making very many parts, it’s actually quicker for the machinist to just clamp stuff in a vice or lathe, put up the drawing and start cutting. Then there’s stuff like this, which can only be done by a computer controlled machine:
There has been a quiet revolution in computer controlled machines and we are seeing just the beginning of it.