H4 EAD to previous H1B

[GCdreamer0612]

I was on h1b for last 8+ yrs with approved i140 - eb2 category. After the EAD rule to have more flexibility I converted to h4 and applied for EAD based on my spouse h1b and i140. Working on H4 -EAD for last 2+ years and have validity til Jan 2020. With recent changes to immigration laws and the rescind of H4-ead rule, I'm loooking for options If the US gov cancels the EAD's for H4 spouses?

1) Can I go back to my previous employer(if they are interested) who applied my GC eb2,  I mean just do change of status H4 to H1b? Will I be considered out of quota or have to go through the lottery system again to apply new h1b and wait till APRIL 1st to apply? 
2) Can I keep my priority date for i140 - eb2 with my prev employer and not redo the whole process for GC? 
 

Please let me know, Your suggestions are appreciated.