TypeError: Cannot access offset of type string on string in date_views_filter_handler_simple

The fatal error only occurs when my view includes an exposed filter that is NULL or is NOT NULL.

@museumboy -
Temporary Fix -
Please do following changes and issue will resolve
In File /home/ide/project/docroot/sites/all/modules/contrib/date/date_views/includes/date_views_filter_handler_simple.inc
Replace

 $element_input['value'] = $this->get_filter_value('value', !empty($element_input['value']) ? $element_input['value'] : '');
 $element_input['min'] = $this->get_filter_value('min', !empty($element_input['min']) ? $element_input['min'] : '');
 $element_input['max'] = $this->get_filter_value('max', !empty($element_input['max']) ? $element_input['max'] : '');

To

      if(isset($element_input['value']))
      $element_input['value'] = $this->get_filter_value('value', !empty($element_input['value']) ? $element_input['value'] : '');

      if (isset($element_input['min']))
      $element_input['min'] = $this->get_filter_value('min', !empty($element_input['min']) ? $element_input['min'] : '');

      if (isset($element_input['max']))
      $element_input['max'] = $this->get_filter_value('max', !empty($element_input['max']) ? $element_input['max'] : '');

I will create a Patch and share with you.

Please let me know if after this changes you are facing similar issue.