Here is my situation;
I got laid off from my company after my I-140 was approved but I-485 not filed.
---- If you have I-140 filing receipt or copy of approved I-140 file your I-485, EAD AP, no need of letter from previous employer for filing I-485.BCIS is not going to check the employer letter l they are just going to check approved I-140 and Fees and nothing more than that. Once you file I-485 and it crosses 180 days you will be eligible for AC21. if not good relations with the past employer no need to inform him that you are filling I-485or your friends just keep quiet till your I-485 hits 180 days then you can send the intent change letter from new employer. Try to maintain your H1 status till you get EAD
I have not got my H1-B X-fer started from another company.
---- I did not understand your statement? Do you have valid H1 and valid I-94? If yes file I-485 ASAP. Are you working now? Did you transfer H1 with other company? If yes then no problem
I consulted a lawyer & he was of the opinion that I can apply for I-485 after obtaining a letter from my old company separately so that after, 6 months, I can change my employers at will and not require any Visa.
---- No need of letter from earlier employer to be filed with I-485. Past employer had submitted letter for you when he filed I-140 and BCIS is not going to ask for the letter with I-485, if they want it then they will ask after 18-20 months at the time of approval when they will check the file but your letter from new employer will be at top of the file before they approve the I-485
Any previous experiences in such a case would definitely help. Do you think that my new employer would have any problems?
----- What do you mean by new employer? Are you working with new employer on H1 status? If yes file I-485 new employer will have nothing to do with your I-485 and EAD AP these applications belong to you. New employer will have no problems. You will need new future job offer letter from the new employer after some time (after 180 days of crossing your I-485) try to get the same/similar job as on your LC that was approved from past employer.
*** First check the BCIS online status of approved I-140 EAC# or WAC, LIN# if it still shows approved then
take the risk of filing I-485 ASAP and dont inform others, just keep quiet . if the lawyer does not agree to file with out letter from past employer search the new lawyer. many have done this and got EAD AP.