7/2 filer, how come rd was sep 4??

My case was transferred from NSC to CSC and CSC sent me 485 receipt with
receipt date as 7/2 several days ago. Today I received a transfer notice
from them saying that my case has been transferred back to NSC. On the
transfer notice, it said the receipt date was Sep 4. I am wondering what
should be the receipt date of my 485. 7/2 or 9/4? Big differnce. Thanks for
timely reply.