With potentially such a large order of coaches in the future, I wonder if Amtrak would go with a joint venture (so perhaps a company such as CAF builds the long distance Amfleets and Alstom builds the inter-city Amfleets) or if Amtrak would ask one company to manufacture possibly 700 coaches!
In the Fleet Plan document some years back, they went into detail about the plan to replace the whole batch in one order, taking 100 coaches a year for six or seven years (More if they started to expand with new routes).
The problem is, how to pay for them? Even if Amtrak-friendly Members controlled the House and Senate, they could vote plenty money to Amtrak for two years. Then another election and things could change again. ;-( So the manufacturer would know that because politics, he might not get paid for the whole order of 6 or 7 years of cars, but only for two. It's hard to get a bargain bid buying only 200 cars over two years, and then starting over with a new Congress and new bids.
I could see CAF building more Viewliner II sleepers, bag dorms, baggage cars, and maybe even diners (if Amtrak started adding routes). But after losing $42 million so far on this contract, I'd be very surprised if they made a strong bid to build coaches.
Meanwhile you return to the notion of joint bids as if it were some kinky sex. I do not expect any joint bids here. No.