National Interest Waiver

My NIW I-140 was approved based on a job, but later, my NIW I-485 was denied because I was not working in a similar role.
My question is:
1. Does the denial of the NIW I-485 rescind the priority date that I got with the NIW I140 filing/approval?
2. In the future, if I am working in a similar role, can I re-file this NIW I-485?
3. Can I use this NIW I140 priority date in my other adjustment of status cases such as PERM-based, etc.?
 

I would appreciate some insights on my H-1B and green card process. Here’s my situation:
I currently have an H-1B visa valid until July 2027.
My company has filed for PERM with a priority date of October 2024.
If things go as expected, I anticipate my I-140 approval around May 2026 (with premium processing, if things go smoothly and I receive my DOL approval around Feb 2026, calculating around 15+ months from Oct 2024).
I’m considering moving to India around January/February 2027, which would be about 180 days after I-140 approval (if that helps retain I-140 benefits even if I go to India; if not, I would be moving earlier).
My questions:
Impact on H-1B if I move to India
What would happen to my H-1B if I joined a different employer in India?
What happens if I stay with the same U.S. employer but work from India?
Returning to the U.S. after H-1B expiration
If my H-1B expires while I’m in India and I haven’t renewed it, let's say that in the future, I will get an employer and want to re-enter the USA. Would the process be expected for the employer, like filing for a change of employer and me getting a new stamp in the Indian embassy, or would it have some additional complications?
I-140 and Priority Date Retention
Will my I-140 priority date remain intact if I am in India and later re-enter the USA for a different employer based on the answer to the above question?
If I get a new job in the U.S. later, what must my future employer do to transfer or use my existing priority date for the new green card process?
 

1. If NIW I485 is rejected. Can we refile I485, or need to start a new NIW case from I-140 stage?

2. NIW I485 is rejected. If I refile the new NIW and it is approved, can the previous NIW's priority date be used for this new NIW's AOS?

3. How will the Trump administration affect NIW I485 cases? Would you suggest any precautions?

4. Can petitioner file multiple NIWs simultaneously with different endeavors?