Okay, I just got off the phone with the Advantage desk. I called to ask what options I had for converting my 27 500-mi upgrades:

1. She gave me the standard answer about them being converted to LP's.
2. I then asked if there were other options, since the LP's were not that useful to me while RDM's would be a much better option.
3. Her response was that this was her 2nd call in a row asking the same thing, and she would note on my account to have someone from their "resolution" desk contact me about what they might be able to do.
4. She did say that she had heard that some had gotten conversions to RDM's, but she didn't know how it was being done.
5. Interestingly, the phrasing she used was that I would be contacted in the next day or 2 with "an offer".

Thus it appears they have at least some sort of process involving options other than LP's, but have not advertised it officially, requiring a call-in.
Now to wait for my "offer"!