There is a sticky that details all the fare classes, but it doesn't look great (if you aren't an SE).

J is full fare business
C is "cheap" business (I cannot think of the technical name)
I is the upgrade class (i.e. the class you want to go into)

So, you cannot upgrade right away and there is only 1 seat up for aerolotto - I'm not sure how popular aerolotto is on this route.