H1-H4-H1...Will approved I-140 be still valid?

[desi5453]

I am on H1B since Aug 2007. I worked in 3 different company so far. Company-A, Company-B and Company-C.

Company-B filed for my GC and got I-140 approved and then I change my job to company-C and got extension beyond 6 years based on approved I-140 of Company-B.

Now, I lost my job, so, will need to go to H4 until get new job.

1) Can I still use my approved I-140 of company B to get extensions beyond 6 year once I get job and transfer back on H1?

2) If my new company process for my GC, can I peruse the same PD based on approved I-140 from company B?

Thanks!