Scanning didn't work everywhere, some CECBs did not clear out the old channel history completely. I did an appended scan on my CM and got duplicate virtual channels, labeled exactly the same. The new one with the picture was accessible by channeling up/down from the original that had no picture. When scanning doesn't work, the FCC recommends 'double rescanning.' Disconnect antenna and do a full scan, then unplug CECB for at least a minute, reconnect antenna, turn on CECB, and scan one more time.
So you got two CMs? Do you know anybody with a different brand you can try out to see if it solves your problem? With my reception conditions, the Zenith and Zat do much better with with motion, as well as with fluctuating signals.
I have a feeling you will get more help with a phone call to the station rather than email.
I'm seeing glitches on otherwise strong stations, and not just on the stations that changed frequency, but I'm hopeful it will settle down. When stations did tower work last summer, or flash cut early, it took about a month to get back to normal. I also have at least one station with a pending application for more power.