As much as we all would like this to be the real situation, unfortunately it's not. AY upgrade priority (both paid=points/vouchers + unlikely operational ones) are based also on the fare bucket of the coach ticket one is flying (and possibly trying to upgrade).

Called to Finnair Customer Center today and asked the prioritation process:
- ticket fare class has no impact (Y and N tickest have same priority)
- no difference if upgrade made with vouchers or tier points
- tier matters (platinum goes first...)
- when 2 same tier level on waiting list
- AY Platinum goes first over other OW platinum cards
- the first in line will get the seat