What happens current H4 application ?

This is a risky plan. Talk to an attorney in private via Skype.

Although this is risky, it is possible. Talk to the company's immigration attorney.

Have you talked to the attorney about KCC PIMS notification to Consulates? Whatever you do ... don't rely on information from NON ATTORNEYS in HR.

How long take the Case when it's Being Actively Reviewed By USCIS ?

What do you mean by 'registered"? Please be more detailed.

I submitted all my supporting documents for my 12 month EAD CARD but I found a small signature difference in my old I-20 ?

You need to be more specific: Please explain the signature difference. Have you talked to your DSO about this?

I601, husband(PR) cannot stay in the US for long periods of time and cannot move here without leaving wife( beneficiary) behind

They need to work with an attorney and a psychologist that speaks their language.

Talk to the people in the facility ... most likely you need to be an LPR or USC.

Talk to a professional tax preparer ... if you provided more than 1/2 of his financial support ... he didn't need to be in the US.

Does the joint sponsor for i864 need to be family related or friends or other family members can sponsor??

No, the person doesn't need to be a relative.

Keep in mind that this is merely an estimate. But, it is encouraging.