I decided to call the CO Elite line about exactly the same issue. The rep said it was indeed odd - we show as Plats - but she couldn't help me. She asked if I'd be willing to be referred to web support, and I'm now sitting on an estimated 20-25 minute hold.

Updated: At the end of 27 minutes in total on the phone, I learned that this problem arose "over the weekend" and that "they're still trying to fix it."

In our case, our two flights are in F and BF respectively so what's on the BP shouldn't matter for boarding, as the agent helpfully told me, but I explained that wasn't the point and that the CO Elite repdidn't know there was a such a problem, which is why I was referred.

In summary, they're aware of it and apparently working on it. I'll just have my photocopied Pres. Plat. card ready as needed.