I have updated the Timeline Entry Page to indicate better what "Service Center" to list. It now reads:

Service Center:
--o for K-1 Applicants where you filed your I-129F
--o for K-3, IR-1, and CR-1 Applicants where your
I-130 was processed (if filed at the Chicago Lockbox
they will transfer the petition to the correct Service
Center and mail you a notice stating where it was sent)