Ok, here goes, first post. I don't think the typical environment in wing structures will be conducive to corrosion of Titanium. A good site is found
http://www.key-to-metals.com/Article24.htm
The design/build process of any large or complex item using new(er) techniques or technologies is bound to produce delays. The choice of a company to either
A. Include a "sufficient" fudge-factor in the quote to account for the majority of these delays. Downside to the customer is at the time of order, so perhaps the company doesn't get the original order.
or
B. Schedule without those delays and push the delivery date as necessary is a marketing decision. Downside here is after order and only damages your future reputation for delivery on-time.