If by the same employer at the same time, I am not sure what USC
The better way is to do EB3 1st and then EB2. Your priority is locked with the earliest date of any approved I-140.
So doing EB3 and EB2 at the same time does not help you.
Besides, one person can only be hired for one permanent job, right?
So doing EB3 and EB2 at the same time does not help you.
Besides, one person can only be hired for one permanent job, right?