If your application has been filed and the priority date is current, USCIS is fairly good at approving the adjustment application in a timely manner (provided there is no need for interview or re-interview). Be diligient in asking your company's atttorney to follow-up with your applications because you do not want to lose your current priority date due to visa retrogression.
You may be required to waiver diplomatic immunity in order to proceed with your adjustment. I had a similar case years ago where we had to complete form I-566 but my client was eventually granted LPR status.
The officer likely updated your biographical form G-325A and/or the I-130. You should be able to obtain a copy of your file through the FOIA process but be forwarned that this can take up to a year to get a response unless you are facing removal in which case you will be able to expedite the FOIA request.