Convert Date to Timestamp and save in woocommerce product metadata

add_action('save_post_product', 'mp_sync_on_product_save', 110, 3);
function mp_sync_on_product_save( $post_id, $post, $update ) {
	if($_POST['_auction_dates_to']){
		$date = new DateTime($_POST['_auction_dates_to']);
		update_post_meta(  $post_id, 'date-testingx', $date->getTimestamp() ) ;
		}
}