Unable to assign perform task ATTACK UNIT to group with task PINPOINT STRIKE or GROUND ATTACK

[Hippo]

As per title, attack unit is simply not there as an option.  Even though in the manual on p.222 - 223 it states:

 

Quote

Attack Unit
Similar to the Attack Group Task, but allows the mission designer to designate a specific unit
within the target group to attack. Applicable to:
Group Type(s): fixed-wing and helicopter groups;
Group Task(s): "Pinpoint Strike", "Ground Attack", "Runway Attack".