Originally Posted by
hoteleksperten
can anyone tell me the cheapest or one of the cheapest upgrade routes with optiontown?
Well it depends on like a million factors

Like your original booking class, the load factor in the class you want to upgrade from and the load factor in the class you want to upgrade into. The time of upgrade bought. The specific route seems to me to be irrelevant. My cheapest upgrade so far has been CPH-NRT from S to Z for only 115 euro (got this upgrade 3 times). I know that SAS only will sell 10 seats in Z as original booking so it really depends upon they see a chance to resell your original seat for a high price.