BT task Move don't get updated destination

The global scenario is: my npc has to follow another npc in formation, so I have a Simple Parallel with a main Move task, and a side task that update the target destination to move to, but I notice that the move task don’t get the updated value from the blackboard until it has reached the old one.

Moreover, the bt is still executed unless the npc reach the target destination while the leader has stopped moving .

How can i fix that?

p.s.: i had to put an “init” task to set the position since if the BB value is not initialized the Move task in the Simple Parallel don’t work even while the side task update the destination.

There is my bt setup for now.