Set field value : Is there way to get only the time value from date time picker custom field?

[Robert Schutt]

I have a simple behavior initializer script that is making a decision based upon the value of a Date Picker field value. The name of the field is "Delivery Planned" and is of type Date Picker.
The form shows the value in the field being 12/13/2017.

The following lines of code:
def l_FormFieldDeliveryPlanned = getFieldByName("Delivery Planned");
String l_sDeliveryPlanned = l_FormFieldDeliveryPlanned.getValue(); //TODO: This is always getting a null even when the form has a value!
a_Logger.debug("Delivery Planned is currently [" + l_sDeliveryPlanned + "]");

result in the following line in the log file:
Delivery Planned is currently [null]

What am I doing wrong to get the value in this field. What object type is returned from the .getValue() call on a Date Picker field type?