It's a good idea. But there is one thing to note. Each such edit will create edit history entry. You should create special user for this purpose so all people will see that it was automated move.
Use to change user in cron script
Secondly you have to create a module and implement cron method in common file (see WatchdogCommon for example)
If cron method will return any content or print to screen it will be logged into cron log.
Our cron provides only interval, not like unix to set specific hour of the day. You should implement this by yourself if you want (For instance store in Variables or Cache that today it's been called).
To retrieve all of the due phonecalls you have to set some filter to retrieve only opened calls, etc.
Utils_RecordBrowserCommon::get_records('phonecall', array('<date_and_time' => date('Y-m-d 00:00:00'), 'status' => array(0, 1)));
Then update record with
Have fun ?
PS. you can play with EPESI from the shell. Execute:
php console.php shell
Or from the browser with EPESI shell at /admin tools