Hi,
sorry this is not possible natively, but you can download and customize import plugin (frontend)
- Download, Install and enabled it (
http://docs.easy-profile.com/index.php/article/import-plugin)
- Open files /plugins/jsn/userimport/userimport.php
- Customize file:
replace from line 66 to line 90 this code:
		if(JRequest::getVar('goimport',false))
		{
			if(isset($_FILES['filecsv']) && !empty($_FILES['filecsv']['name']))
			{
				require_once('parsecsv.lib.php');
				$this->csv=new parseCSV();
				/* TODO ENCODING */
				$content = file_get_contents($_FILES['filecsv']['tmp_name']);
				$firstline = strtok($content, "\n");
				$firstline = preg_replace('/[^A-Za-z0-9\-,;_\r"]/', '', $firstline);
				$content=$firstline."\n".preg_replace('/^.+\n/', '', $content);
				$this->csv->auto($content);
				$this->check();
			}
			else
			{
				$app=JFactory::getApplication();
				$app->enqueueMessage('No file selected','error');
				$this->getForm();
			}
		}
		else
		{
			$this->getForm();
		}
with this:
				if( JRequest::getVar('code','') != 'SOME_SECURITY_CODE' ) return;
				require_once('parsecsv.lib.php');
				$this->csv=new parseCSV();
				$content = file_get_contents('URL_OF_YOUR_CSV_FILE');
				$firstline = strtok($content, "\n");
				$firstline = preg_replace('/[^A-Za-z0-9\-,;_\r"]/', '', $firstline);
				$content=$firstline."\n".preg_replace('/^.+\n/', '', $content);
				$this->csv->auto($content);
				$this->check();
- replace:
    SOME_SECURITY_CODE with some code
    URL_OF_YOUR_CSV_FILE with url of your remote CSV or path of local csv files
- create cron process that trigger this url: 
http://your-domain/index.php?option=com_jsn&view=import&code=SOME_SECURITY_CODE
NOTE: This code is not tested and not supported, this code is provided only for example purpose, you need to have some PHP knowledge to implement this.
NOTE 2: in the latest release you can continue to import CSV files manually from backend