In message , at 15:06:47 on Fri, 14 Oct
2016, tim... remarked:

we already have 30 million sunk cost

what did that pay for?

The project so far?

which as it can't possible be for any construction work must be the
design work.

And I would expect (give the total size of the expected costs) that 30
million would pay for the complete design work necessary. Not just
some holding work with more to come later.

The only reason that you keep such designers on a retainer after they
have completed the design is to make sure that the buiders actually
build to the design and that's going to be a minimal amount of work.

It's most of the work (see the way Cambridge CC botched monitoring BAM
Nuttall delivering the Guided Busway).
--
Roland Perry