I'm in the 212 area code and all local calls need ten-digit dialing. We dial 9 to get out. I have 1212 as an NPA so I dial 9+1212 to make a local (212) call. I noticed one of my vendors programmed a bunch of SPNs whose relevance I don't understand. he programmed SPN 912 through 919, then SPN 92 through 86, SPN 971 through 979 and SPNs 98 and 99. What good do these SPNs do me? No DMI, no anything. Thank you.