Though I don't follow current CHR, I think a couple of things should be pointed out.
1) During the early 1950s prior to the rock and roll eera, songs stayed on the Billboard charts (even though there were only twenty-five listings) for many months at a time. This gradually changed with the advent of rock and roll so that by the mid- and late 1960s, somgs were moving up and down the charts very fast, with some #1s being on the hot 100 less than three months. That began to change in the 1970s, and then really changed, after Billboard started using SoundScan for its hot 100 listings in December 1991. You now had songs in the hot 100 for six months or longer and that hasn't changed despite some tweaking of the SoundScan system to add more rock tracks in 1998 or 1999. So I'm not really surprised by songs staying around for a long time on the Billboard charts now.
2) How do you know that the stations involved have listed these songs as currents instead of recurrents. There was a time when recurrents were being played less than currents but I don't know if that's the case anymore.