NO. USCIS will assign you a new A#. That's what i thought when I made my application... but it came back with a totally new A#. I had 2 OPT EADs with the same A# but guess what? That's will not be your A# I was assigned.
Actually, I now think it's the other way around. I checked here after already filling out my marriage-based I-485 form regarding old vs new A#. I was told both -- that an A# is yours forever, but some posters said that they were assigned a different one later on. However, I've already submitted it without the old A#.
My story: I had an EAD, therefore an A#, based on an employment-based petition years ago. Fortunately, I continued working for my H1/GC sponsor and never had to use the EAD to work for someone else, because the EB-based petition was denied. So my EAD was later on invalidated.
I thought that A# was never mine to begin with, null and void, because the petition associated with it was denied and because I never used the EAD.
So when I applied for AOS based on my marriage last year, I didn't write down the old A# on the I-485 form. I got a new EAD about 2 months later and had a different A# on it. So I thought everything was fine.
But of course, since I'm just oozing with luck
, that was the biggest "beef" that our Immigration Officer had about my case when hubby and I had our interview. Before even swearing us in, the first thing she asked me was, "you had an employment-based AOS filed for you before and you didn't write down an A# here on the form." I told her what I mentioned above, that since the application was denied, that A# is not mine nor valid.
I got the feeling that she was was not very pleasant during the interview because she thought I was "hiding" something, by not disclosing my old A#. She said that because the AOS was denied years ago, I should've gotten a Notice to Appear, yada yada yada..... She wanted to request the old file and see if a notice was sent. I told her I brought all those files and that I never got a notice in the mail. That didn't work, she still wants the files sent from the Nebraska Service Center.
Everything turned out okay in the end, but I thought maybe our interview had been better/decision was made immediately if I had just disclosed my old A# in the form.
Anyway, just sharing my experience with old vs new A# -- probably not the same for everybody......
Good luck either way!