Frequently Asked Questions - AC21 H-1 Portability

AC21 is the name given to a law that provides for several matters including the ability to change jobs while an employment-based green card is pending (I-485 AC21 portability) and to start working for an H-1B employer as soon as transfer petition is filed with the USCIS.

Citizenship for Employees of Consulting Companies who have Projects in Different Cities after Green Card
My Question is after getting green card and leaving consulting employer after 14 months, when person applies for US Citizenship (8 years after getting green card) can USCIS ( knowing that sponsoring company was consulting) asks for client letter, contracts ( like H-1B documentation ) for the period when employee was working with GC employer( after GC approved) ?
H-1B 60 days grace period explained
Lost job recently. Was working on H1B. I am trying to understand how much time I have effectively to find another job and have the H1B filed by next employer. Is it necessary that the H1B “start date” in the I-129 petition be within the 60-day mark ( the grace period) from the last day of job in order for USCIS to grant H1B approval after a layoff?
How does H-1 60 day grace period work?
I am working on H-1B. The job will end in a few weeks. What are the implications of the "60 day grace period" rule that has been created recently?
The Proposed I-140 EAD Rule - FAQ's

Question 1: Redo the PERM or just the I-140. If redoing the PERM again then what's new in this regulation? 

Answer: After 180 days, you can extend H-1 even if 140 is withdrawn.

Question 2: It seems that there is no easy provision for EAD/AP for approved 140 applicants. So is there any point in waiting for this rule or Should I consider Visa stamping is only option for traveling outside US? Please suggest as I waited for a year or long thought they are going to give AP.