给你找个USCIS官方的文件.回复：急问小白兔和各位专家：EB2申请485时

http://www.uscis.gov/files/pressrelease/afm_ch22_091206R.pdf

PRIORITY DATE的内容在26,27页. 下面是28页的例子:

Company A files a labor certification request on behalf of an alien ("Joe") as
a janitor on January 10, 2003. The DOL issues the certification on March
20, 2003. Company A later files, and USCIS approves, a relating I-140 visa
petition under the EB-3 category. On July 15, 2003, Joe files a second I-
140 visa petition in his own behalf as a rocket scientist under the EB-1
category, which USCIS approves. Joe is entitled to use the January 10,
2003, priority date to apply for adjustment under either the EB-1 or the EB-3
classification.

找个强点的律师吧,应该没问题.
你说的那个被推回来的,肯定有其他原因在里面.

如果你交成了485,一定来吼一嗓子,很有借鉴意义.
俺也准备重办EB2 PERM去替换EB3.