In message , Rupert Goodwins
writes

I can't see why the ability to change the destination of trains after
the start of service should have to be bought at the cost of four
hours' extra work. After all, the Northern Line has to reconfigure
itself frequently because of signalling, stock or other problems:

That will be service recovery though - slightly different as they are
trying to get the service back 'on book'.

The main problem I can foresee with your suggestion is that the trains
will end up far away from where they are scheduled to be, thus away from
the relieving driver. You would find more instances of a train having
no driver and having to be put away in a depot or sidings. This would
cause the service to deteriorate even more.
--
Steve Fitzgerald has now left the building.
You will find him in London's Docklands, E16, UK
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