Form I-140

According to USCIS, a letter is acceptable from a financial officer validating 100 employees and ability to pay. However, further information can be requested in case there are other reasons that show an inability to pay. Please keep in mind the employer in the RFE should be given the reason for the request. It is also important to know that USCIS might take the letter from the financial officer due to discretion.

USCIS has not yet finalized the system and has not announced when it will begin.

The regulations state that for ability to pay wages, USCIS will accept copies of annual reports, federal tax returns, or audited financial statements. If the employer has more than 100 workers, a statement from a financial officer of the organization can be submitted to establish the ability to pay the proffered wage.

Answer 1. As long as the job offer exists and the employer is capable of paying the wages, the green card process can go on, even though you are not in USA. You should discuss this matter in detail with your lawyers to better understand the implications. Also, I-140's do not expire.

Answer 2. PD can be ported even if the 140 is revoked by employer. I have a video on this issue 

Currently USCIS is accepting premium processing for certain I-140 categories. In addition to the regular filing fee, there is an additional $1,225.00 filing fee to upgrade to premium processing. If an I-140 is filed with premium processing, USCIS will issue a determination or an RFE within 15 calendar days.

Typically, these are some of the reasons when an I-140 should be filed through premium processing:
1) When an I-140 approval is needed to extend H-1 beyond the 6 years. Please see Rajiv’s blog entry for more information:

The way it works is that the company can file everyone's AOS (Form I-485) together OR they can first get your husband's I-140 approval and leave you to file the last step (AOS) for the family.

Yes, but only if the labor cert is still not time barred (within 180 days of its approval); the employer still has the intention to hire you some time before or after the approval of your green card; and you have the good faith intention of joining them.