Partial Date fields not imported [#2822650]

I have a content type with a Partial Date field (https://www.drupal.org/project/partial_date). The date fields are not importing. It's part of the export, but the values are not imported at all. Here is what the export looks like:

'field_field_semi_annual_reportin' => array(
'und' => array(
array(
'timestamp' => '20160102010101',
'txt_short' => NULL,
'txt_long' => NULL,
'data' => array(
'check_approximate' => 0,
'year_estimate' => '',
'year_estimate_from_used' => 0,
'year_estimate_to_used' => 0,
'month_estimate' => '1|6',
'month_estimate_from_used' => 1,
'month_estimate_to_used' => 0,
'day_estimate' => '',
'day_estimate_from_used' => 0,
'day_estimate_to_used' => 0,
'hour_estimate' => '',
'hour_estimate_from_used' => 0,
'hour_estimate_to_used' => 0,
'minute_estimate' => '',
'minute_estimate_from_used' => 0,
'minute_estimate_to_used' => 0,
'second_estimate' => '',
'second_estimate_from_used' => 0,
'second_estimate_to_used' => 0,
),
'from' => array(
'year' => '2016',
'year_estimate' => '',
'year_estimate_label' => '',
'year_estimate_value' => NULL,
'month' => '',
'month_estimate' => '1|6',
'month_estimate_label' => 'First Half',
'month_estimate_value' => '1',
'day' => NULL,
'day_estimate' => '',
'day_estimate_label' => '',
'day_estimate_value' => NULL,
'hour' => NULL,
'hour_estimate' => '',
'hour_estimate_label' => '',
'hour_estimate_value' => NULL,
'minute' => NULL,
'minute_estimate' => '',
'minute_estimate_label' => '',
'minute_estimate_value' => NULL,
'second' => NULL,
'second_estimate' => '',
'second_estimate_label' => '',
'second_estimate_value' => NULL,
'timezone' => '',
),
'check_approximate' => 0,
),
),
),