My mentor said the only way to fix my pay is to get a competing offer and be ready to leave if they didn’t give a counter. I’ve also seen an American colleague show an FB offer and get a counter which he accepted. But can I do the same while on an H1B visa?
Don't negotiate from a position of weakness. Do it from the position of strength. That fear about premium processing, GC backlog, I140 processing is actually irrelevant for the right talent at FAANG. It is considered a cost to run their business. Nobody will work against your Visa requirements and everyone understands that you may need some additional time. They will consider that as a coat to get the right talent and will support you in reasonable timelines.
Reasonable is the key word. If OP gets an RFE that drags on, FB might actually pull the plug. I personally had an RFE that took 10 months to resolve, and my company (not Amazon) almost pulled the plug. My manager, when I joined, told me that the consulate interview round when I got in was the last one they were going to do before pulling the plug. I would recommend for OP to get his H1B transfer done. That doesn't mean he has to join. He might burn a bridge with FB though if he accepts the offer, has them go through the entire costly and time intensive visa process, and then declines.
Why not?
Because just an offer isn’t worth anything when premium processing widow is closed. I wouldn’t want to risk joining a company on just receipt. In such a case after they get my visa transferred how do I reject them later without burning bridges. There doesn’t seem to be a straightforward way.
Yeah you would burn a bridge.