In Creo 8, you can not change a reference pattern type for a sketched hole, like you could if you had a point pattern. The sketched hole is supposed to replace or be better than point patterns, yet it doesn't work well with reference patterning. One assembly shows the reference pattern when using sketched holes and the other when using point pattern.
This is a pre-Creo 8 reference pattern of a pattern of a pattern. Notice how we can change the reference type from feature, group or both.
This is a reference pattern of a Creo 8 pattern of a sketched-hole. Notice how we can not change the reference type. We should! If this is supposed to be the newer/better method for creating multiple holes, than it should have the referencing capabilities that the older method had as well!