How to configure moveit (Melodic) to get a different joint trajectory for the same end-effector motion in a 7axis system?

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Hello, I am working on a project where a 6axis robot is mounted on a vertical linear 7th axis lift.

Using the the default Planner (OMPL) when a simple vertical linear Cartesian motion from bottom to top is planned using moveit, I find that the software first lifts the vertical 7th axis alone to its full joint limit and then articulates the 6axis manipulator to reach the goal. Similarly , for a reverse motion from top to bottom, only the 7th axis is moved first and then the articulation of 6axis manipulator follows.

Is there a provision to change this behavior of the software.As multiple solutions are possible for 7axis configuration how do we tweak the planner to shift the bias from 7th axis to other options.