I think you should be fine with 485 pending.

You can change your job if your I485 pending more than 180 days. With the current EAD, you can change job. The critical point, not to hurt your application, is your job should be in the samilar field with your Eb3 labor apply. The short gap between your old job and new job is OK as far as it is not too long.

If your 140 is approved, I think you are safe.