ActiveAssembly insert before/after never works

Does anyone else have this problem or know the solution? In AA when we choose before/after the new item is always inserted one item too low. Illustrating this the best I can below. It has actually worked this way since as long as I can remember (started using Percussion 6.7 back in August) but never got around to opening a support ticket or anything about it.

Scenario 1 Start:
A
B <— Insert X “Before”
C
Scenario 1 Finish:
A
B
X
C

Scenario 2 Start:
A
B <— Insert X “After”
C
Scenario 2 Finish:
A
B
C
X