Even though the first reply on this thread had already answered my question, I appreceated the suggestion to use the search function.

Although I have queried the CO search function in the past with mixed results, I went there tonight and entered search for "Platinum/ST Elite Plus." There were 200 replies, many in Spainish. I looked at the first 40 and saw nothing resembling an answer to my question. So much for that approach.

I also went back to several old reservations and saw that CO has been using this term for some time. I just had not noticed it.

Jack