7th Year H1b Transfer - Question

[Ram 143]

I worked for a Employer A, Employer A has obtained an approved form I-140(approved on April/2016) based on an approved labor certification(Priority date June/2014). Then in September 2016 i changed my employer to Employer B, since i had approved I-140 and i got another extra three years on my H1B and its valid till July/2019. Also, i applied for H4 EAD and i got H4 EAD for my spouse and its valid till July/2019. On Jan/4/2017, Employer A revoked my I140. My current employer(Employer B) is not ready to process my Green Card. I'm in 7th year of my H1b. I have below questions:

Questions:

1) Can i change employer to Employer C? If yes, Will i get my new H1b visa till July 2019? Though my I140 is revoked, can i refer to my old I140 and get extension for another 3 years? 
2) What will happen to my Spouse H4 EAD if i do a H1b transfer now?
3) Also, can I use that priority date now with Emplyer C for my 140 filing?

Looking for response..