Adjustment of Status - I-485

Hi,

I am a green card holder since 2013 and I applied for a spouse sponsored green card for my wife in October 2016. She also had a parallel EB2 application from her employer. Since the EB2 wait is longer we are hoping that the spouse sponsored green card comes through quicker. I have a question regarding her case. Her application (spouse-sponsored) became current July 2017 (priority date 4th September 2015). Her application status still says that fingerprint was received on October 2016 and her case is with the NBC. We hope the case will be soon transferred to the local field office in New Jersey (we reside in New Jersey) but the wait has been frustrating since the local field office has a further one year delay. She also has her EAD/AP combo card (valid for one year and expires in January 2018) but also still has a valid H1B VISA (which expires in December 2017). Recently, she learnt that her employer might be laying off people so we are a bit worried because if she is not able to find a new job, then would her EAD allow her to stay in the US or like the H1B VISA she needs to evacuate the US in 2 weeks? We believe she can continue to stay in the US since her EAD is spouse-sponsored and not from her EB2 application. Also, we were wondering if she can also change her company since the EAD is spouse-sponsored and is perhaps not bound to her current employer?