In my case, I just called in and the rep said I couldn't get the original rate, and he transferred to a supervisor that said the same thing. I asked the supervisor about KM 6115, and they said they couldn't find any document with that number, so that must be gone now.

He said he did find a KM 10759 that explains that for reservations made after September 14, Points Advance doesn't reserve the rate, just the room. When I pointed out that my reservation was made before September 14, it finally seemed to click in his head, and he went looking for further instruction. He eventually found KM 14275 which explains that the rates when booked are supposed to be honored for pre-9/14 reservations and explains how to do that.