Chiangi,
Was that a waitlist for coach or for business upgrade?
I am Platinum Elite too and I think the best benefits / recognition begain once you start US domestic... not in Asia... the operational upgrades chances are so miniscule...
When I do have Y ticket, I never have problems in getting a seat ..... However, the Q tickets from Singapore usually do not allow for waitlist .... My waitlist for M class from Tokyo to Honolulu just cleared so basically for a coach seat, my waitlist percentage is about 100 percent ....
Just go to the airport and wait ... they will give you a seat ....
BTW, what are your operational upgrade success rate?
What are your upgrading with miles success rates?
I have got many lies from the NWA staff at Changi .... " Business is full, I am sorry" and then I walk into a half empty C cabin