Company A filed I140 in EB2 category and it got approved with PD of May 2006.

Then moved to Company B which applied I140 in EB3 and got approved with PD of Apr 2003 [This is done through labor substitution]. Filed AOS in July 2007.

Later initiated EB2 interfiling process through Company A on the existing Company B's AOS petition, thereby converting it to EB2 with PD of Apr 2003. Very recently I got my GC approved. Currently I'm working for Company B.

Question: Who is supposed to be my GC sponsoring employer in this case, that I need to work for after receiving the plastic card ?

Thanks.