Is damage rolled for once per area of effect spell, or rolled once per target?

I’m trying to figure out whether you roll damage for AOE spells as a group or individually in the Fantasy AGE system. I can’t find any explicit mention in the rulebook.

For example, the spell flame blast creates a 8×2 area of fire. Anyone in that area takes 2d6+1 damage unless they make a successful Acrobatics test in which case they take 1d6+1.

In this case there are at least two damage rolls going on, but it’s unclear if there are just two separate values for damage pre-rolled for the whole group, or if damage for each target is rolled separately.

If anyone can point me towards some applicable rules (or confirm that this is something the GM has to rule on) that would be wonderful.