I was working with Company A where I got my 1-140 Approved. I left Company A after a year and joined Company B on new H1B for a client . Last year Company A filed for my I-485 and I got my EAD. My priority date is current now. Should I join Company A immediatly on EAD or after getting Green Card to maintain integrity of GC ?

My client will remain same with only difference being with Company A, I will be Corp-to-Corp to Company B. Will this cause any issue ?

Also my salary with Company A though will be more than wage specified on Labor , but will be less than Company B providing currently. Is that an issue ?

Thanks for your help.