Thanks for all your kind replies!

NO LUCK.

I was indeed calling the main office in Bangkok, during office hours (to make sure that I could get hold of the ROP staff and whoever authorises this kind of things was there).

I tried again today and had a lengthy discussion with the agent. In summary: not possible. He told me that he could try his best and put me on hold for about 15 minutes. In the meantime I was monitoring my ticket on CMT and also the ROP account and noticed that:
- he deducted the miles
- the segment was eliminated from the e-ticket and rebooked in first (within the same booking, but no longer part of the ticket)
- the segment was then rebooked in business

He came back to me saying that his superiors denied the authorisation, because the flight has reached the "quota" of award seats (ie: there must be an obscene amount of award pax on that flight). I told him that I could take the earlier flight or the first one the day after, but he said that he already tried to ask and that wouldn't be possible either.

I explained to the agent that this was the first time it happened to me and was a bit disappointed, especially seeing that they still have P class availability. He was apologetic, but it appears they are getting stricter. He also suggested to keep calling back, but honestly I don't have any more time to spend arguing on the phone.

Again, it is something that had never happened before. It indeed seems there has been a change of rules. This is a major disappointment: I always thought (and clearly stated) that the major benefit of ROP was their willingness to bend the rules for gold members. Now the program has suddenly lost all my interest; won't certainly renew the status.


(by the way, in the process I now have a booking with the second leg no longer ticketed... just a reservation in business... rather disappointing)