Thank you so much for this clarification Marooned42
Finally got it, thanks a lot for this clarification Marooned42.
I believe the A# you are referring to is the A(lien) file number. Each applicant is assigned one, yes. However, visa numbers are different. VNs are assigned when an I485 application is ready to be approved or has just been approved - the idea being that each approval reduces the available visa number total by 1. There is no limit to A numbers. Visa numbers, however, are subject to quotas as specified by immigration laws.
Finally got it, thanks a lot for this clarification Marooned42.