Seems Finnair now has launched so one can see BC upgrade availability through the booking process for Gold and above. Trying it out its an annoying process though as one needs to search one date at a time, click on the flight and go to a specific tab.
Clicking around for a while I concluded that HKG-HEL has ZERO availability and only allow wait listing on all upgrades. For other destinations like BKK there is availability to straight away upgrade to BC. Why does Finnair keep punishing me as a HKG regular flyer?