I forget when exactly, but some time before the last election C-SPAN changed the descriptions of the phone lines. It had something to do with, if I remember correctly, that large majority of the calls C-SPAN was getting were of the same opinion, and they found that when they reworded the descriptions of the phone lines, they got more diversity of opinion in the phone calls.
I saw one of the hosts on Washington Journal explain it once to a caller who was irate that they had changed the phone lines.