回复：I-485 was denied

1. You are not able to come with either F1 or B visa again since you have filed I-485 before. If you leave states, the only way you can come back is with immigraion visa or H, L visa which is quite impossible for nurses.
2. The best way is to file another 485 before 11/10, a new I-140 maybe required if you changed employer. That will give you about 1 year to get visascreen certificate.

Interestingly, most people are complaining about 485 delay, but for nurses, processing of I-485 seems too fast to get visascreen in time.