Can I change my employment within 180 days of my I140 approval after the new I140 rule changes?

[Vijay Singh]

1) My I-140 was approved on Feb, 22 2017 and now I am planning to change my job to another company. 
My employer has a policy of revoking the I140 application within 60 days of my job termination. Will I loose my priority date if I leave my current employer within 180 days of my I-140 approval and employer revokes the I-140 application? 

2) I am in 6TH year (04/03/2018 - full 6 years) of my h1b and my I140 application was approved on 02/22/2017. Since premium processing is suspended for next 6 months, so if I change my job and my employer revokes my I140 application before the next employer gets my h1b visa transfer approved. Will I get h1b ext for next 3 years or only till end of 6th year which completes on 04/03/2018. 

3) If I stay with the same employer for 180 days after my I 140 application approval and priority date is not current yet. Can I change my employer(I140 applicant) and get my h1b visa ext from next employer without filing new PERM/ I140 application. 

4) And can I get my h1b extensions from future employments based to the same I140 or do I have to file new I140 applications every time I change my employment.