Following on from what you have said, can I do this:
Top line of code add this:
<?php
date_default_timezone_set("Africa/Johannesburg");
?>
For registration date:
<?php echo date('Y-m-d', time()); ?>
For expiry date - exactly 1 year later:
<?php echo(date("Y-m-d h:m:s", mktime(date("h"), date("m"), date("s"), date("m"), date("d"), date("Y") + 1))); ?>
Thanks