About H4 using EAD to work

My lawyer specificly confirmed to me that H4 can use EAD to work and not lose his or her H4 status even if the I140 and/or I485 is rejected. It seems to be different from what I got from this forum. The lawyer told me that if H1 used EAD to work, he or she will lose H1 status. My understanding now is that if you are in H1, your spouse is in H4 and you applied GC for you and your spouse based on your employment, you are at risk to use EAD because you lose you H1, but your spouse can use EAD to work without losing H4. I am not sure that it is correct. Can anybody clearify this for me?