Automtically creating new redirects and alias on node_save
Pathauto should automatically create a new alias with the updates (unless you have it turned off on the node). pathauto.module lines 519-522:

// Skip processing if the user has disabled pathauto for the node.
if (isset($node-&gt;path['pathauto']) &amp;&amp; empty($node-&gt;path['pathauto'])) {
  return;
}


The Global Redirect module can then provide 301 redirects to the new URL alias.