CBP wont change it. CBP only defer things that are considered to be mistakes
made by the boarder officers. there is treaty between US and China that
makes CBP officer give you I94 only valid 6 months prior to your passport
expiration date. you are luckly that they gave you the I94 expiration same
as yr passport one.
however, there is a provision rule called "245(k)" that allows an individual
to overstay their status for up to 180 days and still be allowed to file
for adjustment. in another word, if you file yr 485 case within 180 days
after your I94 expires, you are fine.
BTW, USCIS thinks I94 on yr H1b797 override the one CBP gave you. this is
not agreed by CBP.