My ND is 04/02/01 and my case was looked at today as well.
My guess is they are finally getting around to entering the fingerprints results. I think people who were sent FP notice last year, now their accounts are being updated. The reason I say that is because when I talked to FBI few months ago, they told me that my FP results were sent back to USCIS the very next day. This is the first time they updated the date after they sent me FP notice.
Now here is my other wild guess and this one is pretty optimistic. I think USCIS might be holding out on the approval and getting things ready to approve. Now that Ngwanyia Ashcroft settlement has been finalized, they will flood us with approvals so that they can get credit towards the extra 8000 applications that they have to approve in this FY. If that is the case, we should see a huge jump in the processing dates at the end of June.
Thanks