In what stage in the green card process a spouse can start working?

[naida]

I've been working in US for 4 years on L1B visa. My visa expires next year so my employer wants to apply for H1B for me in april and wants to apply for green card today.
Since I'm still on L1B, my wife has a work permit till Jan-2019. But, once my visa will be converted to H1B in september, she won't be able to work when the work permit ends.
My question is, in what stage in the green card process my wife will be able continue to work? I heard that once I140 is approved she can work even though she's on H1B visa.

[krypton9591]

I've been working in US for 4 years on L1B visa. My visa expires next year so my employer wants to apply for H1B for me in april and wants to apply for green card today.
Since I'm still on L1B, my wife has a work permit till Jan-2019. But, once my visa will be converted to H1B in september, she won't be able to work when the work permit ends.
My question is, in what stage in the green card process my wife will be able continue to work? I heard that once I140 is approved she can work even though she's on H1B visa.

from what I know as soon as EAD card is in hand they can start working or looking for work.