<div class="td-header-rec-wrap">
    <?php
    $tds_header_ad_title = td_util::get_option('tds_header_title');

    // show the header ad spot
    if (is_category('Fashion')){
        echo td_global_blocks::get_instance('td_block_ad_box')->render(array('spot_id' => 'custom_ad_1', 'spot_title' => 'your custom title text'));
    } else {
    echo td_global_blocks::get_instance('td_block_ad_box')->render(array('spot_id' => 'header', 'spot_title' => $tds_header_ad_title));
    }
    ?>

</div>