H1b transfer to new employer -- Status of H4EAD?

[new2nyc]

I am on H4 EAD from Aug-2015, renewed last year. My husband was let go and Aug-31 is his last day with current job. He found a new employer, but there will be a gap of few days between visa transfer.
Say, his last day with Employer A is Aug-31
His H1 will be terminated on Aug-31
His new company files for H1 transfer in first week of September (Sep-05)

Questions:
1.  What will happen to my H4 status and H4 EAD? 
2. Do I need to apply for H4 only ,I can continue on H4 EAD once my husband is back on H1? Or do i need to file for h4EAD again?
3. If my EAD is invalid till my husband gets a job, can i start work on Sep-05 or do i need to wait to apply for h4 and then i can start working.
Note: I will let my employer know of my situation today, as this is the new development.

Appreciate any suggestions/ pointers!

Thanks.