FA closing periods(R12.1.3)

Dear Freinds

I am working on a project wherein we need to create more then 200 FA books.But client requirement is that all 200 FA books should be accessible through centralised access with the set of not more then 5 users.As I understand that I can create security by book profile and assign , say for example , 50 books per profile and assign the same to responsibilities.But my queries is... can we control month end process (running depreciation and create accounting process in batch of 50 books simultaneously.

In otherwords can I close all 50 books at a single click.

My second query is regarding data flow from FA to GL.I know in R11.5.10.2 FA send the data to GL throuhg gl_interface but at lot more places I have seen written for R12 architectuire that FA send the data directly to GL_JE_HEADERS and GL_JE_LINES.This statments is confusing me as what I understand even in R12 first data should flow to SLA and then to GL.Can somebody please clarify this.