Question: H1B status when H4 starts working with EAD

sorry if this is one of the FAQ

My 140 is approved, 485 pending...endlessly.

Could I still maintain my H1B non-immigrant status, if my wife applies and starts working with her EAD?

Or I will be required to get an EAD and surrender my H1B?

another question, my 6-year H1B will expire in 8 months, should I extend it to the 7th year, or should I start the EAD? what's the advantage/disadvantage to do so?

any comments are appreciated, thank you.