Where to file EAD renewal - New instruction is confusing

The new Rev. 02/12/10 I-765 instructions was not clear as to where to file
the EAD application for the c(9) category.

It says file at the UCSIC Chicago Lockbox facility if your response to
Question 16 is: (c)9 AND you filed your Form I-485 with the USCIS Chicago
Lockbox facility, and your receipt number begins with "MSC".... (see
instruction page 9).

I am in the c(9) category, but I did not file I-485 with the Chicago Lockbox
facility, then where should I file my EAD renewal? I used to file it with
the Nebraska Service Center, but it was no longer listed in the new
instructions.

Any ideas? Thank you!