As I told you, your attorney is absolutely right that what he said....
Here are definitions :
EAD : Its totally belongs to you, USCIS is giving you authorization to work for any employer in US, irrelative of what they (employer) are sponsoring like H1B, GC or Other Immigration related petitions....
so you can work for anywhere, anykind of job.....but in US.
GC : US Employer is saying to USCIS that he is willing to hire one person for his company requirements...
It means he satisfied your past experience until he filed Labor for you....after that he don't (shouldn't) care about your employment....
In case, if it is denied becaz of your present employment (at the time of GC approval), then he can argue that he will provide job once you get GC...
Important thing is, he don't need to provide employment until you get greencard.... also he don't need to hire you once afer you get GC.... but second thing, he should not do intentionally....
Now see how it works....
"A" applied GC petition for you...
you'll get I-485 Receipt (so until here you should be staying in legal in US).. from this RD it provides you to stay here, no matter you work or sitting idle....
You'll get EAD after couple of months... means US gave you permit to work something if you want... otherwise stay legally.. but you should not be having Public Charge....
With EAD you joined "B" and doing some other kind of work....
At the time of approval USCIS is asking you to submit Employment letter that shows still you have an employment required in US... so you have to get this letter from "A" *(if still they are supporting you), OR anyone of "B","C","D" etc.. but this (B,C,D) company should have same and similar kind of job (as "A" suppose to provide).... and hire you permanantly
Is it clear !!!!!
As usual here is the quote from Swamy Vivekananda...
"Whatever you think,that you will,be. If you think yourselves weak, weak you will be; if you think yourselves strong, strong you will be"
It means be confident, you'll get whatever you try to get....
