It looks like I spoke too soon. It's actually not working afterall.
I changed the following 3 lines in the code:
$WAFV_Redirect = "" . $_SERVER["PHP_SELF"] . "?sent=true";
$GoToPage = "".(rel2abs("../contact.php",dirname(__FILE__))) ."";
<form class="sample" id="sample" name="sample" method="post" action="<?php echo($_SERVER["PHP_SELF"]); ?>">
When I submit the form I receive the information and contact.php reloads but the div doesn't show, ie.
<?php if(isset($_GET['sent']) && $_GET['sent'] == "true") { ?> <p id="confirm" style="background-color: #00274c; color: #fff; height: 30px; line-height: 30px; padding-left: 10px; margin-bottom: 15px;"> <strong>Thank you for your enquiry. We will be in contact as soon as possible. </strong></p><?php } ?>
Really appreciate any further advice.