dependent EAD with a seperate GC process going on

Hi All, I have a dependent EAD through my husband's GC process. I have a separate GC process going on with the same employer as my husband. My GC process is I140 approved(more than 180 days passed after I140 approval). Now, I want to join a company fulltime, but I still want to hold on to my separate GC process, just in case in future something goes wrong with my husband's GC. But now I am not sure if the employer would keep my GC process with him if I choose to join some other company fulltime. Please help me out as to what can I ask the new employer to do that will save my GC process. Or is my GC process not cancelable as it already passed 180 days after I140 approval? I want to save my PD. Right now me and my husband are both with the same employer and I consider it very dangerous as if something happens both of our GC will be in jeopardy. Please help me out. Thanks in advance