1. I see few cases where CIS has sent an RFE to ask for Employment Verification Letter (EVL). When does this typically happen? 2. For cases where in the EVL was already sent along with the I-485 application, what are the reasons usually for CIS asking EVL again? 3. I had taken an Infopass few months ago, and they had said my I-485 application is pre-adjudicated. What does this mean?
1. EVL can be asked for at any stage of AOS/I-485 process. It is REQUIRED when you submit the 485, but thereafter it is discretionary.
2. The main reasons are that USCIS has to make sure you still have a job and the job is "same or similar" to what was described in the labor cert (or I-140 for EB1).
3. This means your application has been reviewed and adjudicated to be approvable. So, USCIS is just waiting for the visa numbers to be current.