display link after finishing coutdown time
Have a look at the project page. It says

You can use jQuery Countdown in two different ways, one is using theme('jquery_countdown'), the other is using jquery_countdown_add(). 

In the following example, we display an alert box saying "You are done!" after counting down from 10...

&lt;?php
  echo '&lt;div class="countdown"&gt;10 seconds!&lt;/div&gt;';
  jquery_countdown_add(".countdown", array("until" =&gt; 10, "onExpiry" =&gt; "finished"));
  drupal_add_js("function finished() { alert('You are done!'); }", 'inline');
?&gt;


You can use the above example to achieve your requirement.