The refund rules should be clearly stated at the time of booking and they may be different depending on how you book the tickets.
When I look at Business Smart (through sas.dk) it's stated they can be changed and refunded for a fee (used to bee DKK600 in Denmark), but this might be different if booked from other countries or through other booking sites.
SAS Business (not Business Smart) is stated to be changeable within the same booking class and full refundable, or partly if part of the trip has been used. All without fee. But again. This might be different through other booking sites or from other countries.

I always use the SK websites when booking SK flights as the rules are clearly stated here at the time of booking, and all fees are listed before typing in any credit card info.