the NVC can take several weeks to "update" the petitioner\'s status on an I-130
Assuming you included a copy of the receipt notice with your Naturalization Certificate copy, it may take several weeks for the NVC to connect the Naturalization Certificate copy with the I-130\'s file and an additional several weeks for the computer to get updated, even though the I-130 will be transfered immediately to the processing line for US citizens (when combined with the file).
Several attorneys\' websites post the service centers\' processing times for I-130\'s. check one to determine the advantage in processing times. Your next contact should be the I-130 approval notice (or a request for additional evidence), when it will be forwarded to the National Visa Center.