caldera_forms_private_upload_directory.php

<?php
add_filter( 'caldera_forms_private_upload_directory', function( $directory, $field_id, $form_id, $transient_id ){
  //IMPORTANT -- Change this to the ID of your field, or remove this conditional to affect all fields.
  if( 'fld111' === $field_id ){
    //see: https://developer.wordpress.org/reference/functions/wp_get_upload_dir/
    $uploads = wp_get_upload_dir();
    $directory = $uploads[ 'basedir' ] . '/somepath';
  }
  return $directory;
},10,4);