diff --git a/php/class-post-type.php b/php/class-post-type.php
index aa589fdc..413f710a 100644
--- a/php/class-post-type.php
+++ b/php/class-post-type.php
@@ -723,7 +723,7 @@ public function handle_snapshot_bulk_actions( $redirect_to, $do_action, $post_id
 				$compare_a = $a->post_date;
 			}
 			if ( '0000-00-00 00:00:00' === $compare_b ) {
-				$compare_a = $b->post_date;
+				$compare_b = $b->post_date;
 			}
 			return strtotime( $compare_a ) - strtotime( $compare_b );
 		} );