In article ,
[D Stock referb]
Not that many. 6 or 7? In the lifetime of a train thats nothing.
It started in 2005; the trains will start to be withdrawn in 2015
IIRC, so it was at around the 2/3rds mark of the stocks life, and
will be in service for a decade.
Doesn't sound unreasonable to me.
--
Mike Bristow