Change Sponsor Employer after Final Green Card

[bobon]

I don't find a specified rule where new green card holder must work for sponsor employer for 6 months after getting a new green card or I-485 Approval date in USCIS or DOL website but most of the immigration lawyers have mentioned better to stay with your current (GC sponsor employer) for 3-6 months which would help you for US Citizenship.

Few lawyers said USCIS  can revoke your green card after 5 or 10 years if they found you left your sponsor employer immediately unless employer laid off you  within 3 months but better to join in New company with same job profile what you have right now after 6 months.

I am afraid about leaving my current employer for above reasons!

How soon can I change my employer after getting my green card(Final Not EAD)?

Shall I have to inform USCIS?

Does it have any negative impacts to my citizenship in future?

Can I join in progressive career on the same field using my past experience and keeping 70% my existing job profile?

Please advise.

Thanks in advance