Oh my freaking god! Blizzard's reply simply just stated that I had an SEA license instead of one from the Americas... no where did they even consider the fact that I'm in Australia with a licensed purchased from a retail AU store, not Singapore, and could probably do with changing the currency. Would prefer to change the currency as AUD$39.95 is still cheaper than SGD$49.95+ CC currency conversion fee.
On the other hand, I'm in no rush to play HOTS... just wanted to use up some Bliz bucks on something worthwhile rather than let it sit there. I'm only after the campaign. I'll probably wait for retail to drop in price.