Help needed for priority date, to PJiang and other experts

My I-140 based on NIW(EB2) was approved in 2005 and the priority date is 5/4/2005. But due to regression and name check, my I-485 is pending so far.

Thus this pushed me to file another I-140 based on EB1B. I have a couple of questions. 1. When can I request the I-485 transfer? 2. When I-485 is transfered, what is the priority date, old I-140 priority date (5/4/2005) or new I-140 priority date? 3. Do I need to request priority date transfer from old I-140 to new I-140?

Thanks a lot.