You can use the Pole offset settings found in the Chain IK constraint to change the Pole’s position. These values are added to the Pole object’s position.

To create a Pole offset:

1. Double-click the Chain IK constraint in the Scene browser to select it.
2. Open the Properties window. The constraint settings display.
3. Expand IK Settings > Pole Offset and set a value in the Pole Offset X, Y, or Z fields for the desired effect.