Robert wrote:

.......But what
happens to the Greenford service? If it reverts to being a shuttle
will it turn round at Ealing Broadway or in the old milk dock at West
Ealing?

It does become a shuttle into a new bay platform at West Ealing, there's
stacks of detail on the Crossrail information website:

http://tinyurl.com/65r3r9

pp 7/8 refers, very large file though unfortunately.

HTH

Paul S