This is not a supported modification to power store, so I really cant give to much help on this.
the code for the recordset on the results page is:
php:
$query_WADAProducts = "SELECT ps4_products.*, coalesce(GroupingID,ps4_products.ProductID) AS GroupingID FROM ps4_products LEFT OUTER JOIN ps4_productoptions ON ps4_productoptions.ProductID = ps4_products.ProductID " .((isset($_SESSION["WADbSearch1_Products_Category_Results"]) && $_SESSION["WADbSearch1_Products_Category_Results"] != "")?"LEFT OUTER JOIN ps4_productcategories ON ps4_products.ProductID = ps4_productcategories.ProductID":""). " WHERE ProductLive = 1 AND (ProductStartDate IS NULL OR ProductStartDate <= CURDATE()) AND (ProductEndDate IS NULL OR ProductEndDate >= CURDATE()) " . ((isset($_SESSION["WADbSearch1_Products_Category_Results"]) && $_SESSION["WADbSearch1_Products_Category_Results"] != "")?$_SESSION["WADbSearch1_Products_Category_Results"]:"") . " GROUP BY coalesce(GroupingID,ps4_products.ProductID) ORDER BY".$_SESSION["orderAdd"]." ProductName";
the last part:
ORDER BY".$_SESSION["orderAdd"]." ProductName"
sets the ordering, you could change that to the start date using:
ORDER BY ProductStartDate"
