options-state-patch.diff

@@ -400,6 +400,9 @@
         return this.each(function () {
 
             if (typeof options == 'string') {
+                //restore options state before public method calls
+                tagManagerOptions = obj.data('tagManager-options');
+
                 switch (options) {
                     case "empty":
                         empty();
@@ -531,6 +534,9 @@
             } else if (tagManagerOptions.hiddenTagListId != null) {
                 prefill($('#' + tagManagerOptions.hiddenTagListId).val().split(baseDelimiter));
             }
+
+            //store options state for further public method calls
+            obj.data('tagManager-options', tagManagerOptions);
         });
     }
 })(jQuery);

This has saved me, thanks Dincho!