It's probably now safe to admit this. During the merger there was a very short period on a certain day where the RewardsPlus site came back after status had transitioned, but before changes had been made to recognize that the new Platinum was not the same as the old one, and somehow my account linking and matching was validated so I got MP Silver from my post-merger Platinum status that converted from MR Gold status that I got free from the Ritz-Carlton credit card.
I've been fortunate to make use of the lower cancellation penalties of MP Silver for the past five months or so even though I should not have it at all. Still, it'll be a bit sad to have it disappear at the end of the month. Curious to know now if anyone else was able to do this.