I'm involved in a massive project that is turning 70+ antiquated systems into one system for a large company. The whole team and the executives at the company realize that this is a huge undertaking and that some things will be different for many people and there is no way around it. I'm one of the 5 UX/Information Architects on the project and just the other day I realized that we're going to need help documentation and a help interface.
Right now everything is in flux. Since there are so many systems there is no current-state understanding of the entire system and how everything connects. As we develop requirements and document the functionality that the new system needs to have we start finding more functional requirements that we didn't know about.
I really can't fully state how big this application will be for this company. As a result I can see right now that help will be crucial when we transition over to the new application, but I don't know when we should start working on the help documentation. I really don't want to wait until the application is finished or close to finished because I know the majority of the project team will sweep it under the rug and say that training will cover it.
Basically, my question is when should we start collecting help documentation, and what is the best way to document it as the project progresses?