Christian, ignore my previous email re: time span for the project. Having looked at your code, I see that you make use of the SCHEDULED and DEADLINE properties of the top headline. This is obvious (in hindsight). So this works.
I now have a further problem which I will email later when I am back online. I am currently on the train home without Internet access (which means that this email may cross any from you or others). Thanks again, eric -- : Eric S Fraga, GnuPG: 0xC89193D8FFFCF67D : in Emacs 24.3.50.1 and Org release_8.0.2-68-g40635b