I remember reading a while back that somebody's score jumped because of a small typo.
The bureau was reporting 9/12 instead of 9/1/2002
When it was fixed, their score shot up.
I would look for any and all typos. Did any fields change at all? Any dates change? What about balances? Do you see anything that was reporting as $0 no reporting as $.00.0.
I do believe that tiny little things can cause huge problems on reports. I'd go over with a fine tooth comb old reports vs new reports and any of the tiniest changes, I'd make a note of it. It could be something you didn't notice. Maybe something as small as a PAID vs PAID AS AGREED.