help on 485! dan712 & anybody!

Sorry, I can't input Chinese this time.

I filed my I-485 with NSC in 09/2002 and have not heard
anything from them except had fingerprints done in 12/2002. I was the only applicant, now I recently got married (11/2003) and my wife is going to join me on H4 (I am on 5th year of H1) very soon. My company lawyer has suggested to file her AOS
as soon as she joins me, but how likely will this trigger a local transfer to Chicago office where I live? (Because I heard that if you have been married less than 2 years before submitting AOS together, it is very likely, almost certain that INS will transfer your case to local office). Chicago is notorious
for their slowness, after waiting for so many years, I don't want to have another factor to delay the processing. Are there any suggestions you guys can give us? I have been working for the same company ever since the whole GC process started, so without this complication, I would expect a rather
straightforward approval.
My question is: If we hold off my wife's 485 application until I get approval, what is going to happen to her status? I know that
she probably won't be eligible for H4 anymore.
Would they be better off if we change my wife's H4 status in the states to F1 and then submit
her 485 after my approval which hopefully to be before
the end of this year? If I get approved before she submits 485, she probably has to go through the family based application for greencard holders, right?
So what are our options? anybody with experience and/or suggestions please help. Really appreciate it.