H-1 to H-4 and EAD

[Jhansi]

Hello all, 

I am currently on H-1 B visa, and I am willing to change my status to H-4 and apply for EAD (I am eligible for H-4 EAD based on my spouse's status) as well. Below are my questions, 


1. what would be the total processing time for COS from H-1 B to H-4 (within USA) and filing EAD concurrently. 
2. Do I need to maintain my H-1 B status until H-4 has been approved? 
3.Can we travel out of the USA while EAD is in processing. 
4. Or can I travel to my home country to apply for H-4 visa ? And once my H-4 visa has been approved, can I file for EAD while I am still in India? 
5. which process is quicker; H-1 to H-4 COS in USA or in India? 
6. Does EAD has a seperate validity or will it depend on H-4 validity? 
7. Do we need to apply for EAD multiple times after each H-4 expiration. 

Please clarify my queries. Thank you for your time