It's probably also because the further you get into kept yesr the busier they are going to be. They can probably pre-prepare a ton of the documents and then just fill in specifics later, at least I would assume so. Seems like they really just want to button up what forms they are going to need and make sure you have a list, etc to provide them as they become available.

Thats just my thoughts though I'm not a cpa nor do I run a business.