FMB Stuka Leader/subordinate dive bombing

[Racetrack]

Hi guys I have a problem with the Stukas.

I have a mission with 9 squad of Stuka ( 3 planes for each ), i divided in group of 3 squads with one making the "leader" and two following, so,

Firts Squad )1 Leader (3 planes) --- 2 subordinate (3+3 planes)
Secondo Squad) 1 Leader (3 planes) --- 2 subordinate (3+3 planes)
Third Squad) 1 Leader (3 planes) --- 2 subordinate (3+3planes)

The waypoint of the subordinate squads have for target the waypoints of the leader squad, so the result is a perferct formation while
flying to the objective. This is very fine!
BUT
When they all reach the target ( British convoy ) i have a problem, i've setted for each squad 1 different target, so 9 squad ---> 9 target.

The problem is that they are dive bombing ALL on the leader Objective. So the firts two subordinates squad ATTACK the first leader Obj,
the second two subordinate squad ATTACK the second leader Obj, and the subordinates leader squad ATTACK the third leader Obj..

WHY?????