If you exclude booking classes, the upgrade priority list would be:
1. SK Pandion
2. SK Gold
3. *A Gold
4. SK Silver
5. *A Silver
6. SK Basic
I'm pretty sure that booking class is a factor (I know it is on i.e. LH). Economy seems to be completely sold out on your date, so they will have to upgrade pax (either op-up or through Optiontown). Since H-class (if booked with SK prefix) is a pretty decent booking class, I would say that you have good chances for an upgrade - at least to Economy Extra.