I accidentally activated a feature code on an extension. I think it was a feature code? Anyway, it toggled the BLF for the user on the handset and it would not turn off. This was reflected in all other handsets that were programmed with that user BLF.
I was able to make it go away by deleting the extension, removing the handset from Endpoint Manager, factory defaulting the phone and rebuilding everything. Also, I had to push out the templates to all of the phones.
I was convinced there was an easier way.