diff --git a/ns/NS_Tests.ttcn b/ns/NS_Tests.ttcn
index b45ab91..c08f877 100644
--- a/ns/NS_Tests.ttcn
+++ b/ns/NS_Tests.ttcn
@@ -752,6 +752,52 @@
 	f_clean_ns_codec();
 }
 
+/* 1. do SNS configuration
+ * 2. add a bind
+ * 3. receive the SNS_ADD
+ * 4. before answering the SNS_ADD, change the weight via vty and remove the bind
+ */
+testcase TC_sns_sgsn_add_change_del() runs on RAW_Test_CT {
+	var PDU_NS rx;
+	var NSVCConfiguration nsvc_cfg;
+
+	g_handle_rx_alive := true;
+	f_init_vty();
+	f_init_ns_codec(mp_nsconfig);
+	f_init_ns_codec(mp_nsconfig, 1);
+	f_outgoing_sns_size(max_nsvcs := 4, num_ip := 4);
+	f_outgoing_sns_config();
+	f_incoming_sns_config();
+	activate(as_rx_alive_tx_ack());
+	f_vty_config2(NSVTY, {"ns", "nse " & int2str(g_nsconfig.nsei)}, "ip-sns-bind local2");
+
+	/* rx SNS ADD */
+	nsvc_cfg := g_nsconfig.nsvc[1];
+	if (nsvc_cfg.provider.ip.address_family == AF_INET) {
+		var template (omit) IP4_Elements v4_elem := { ts_SNS_IPv4(nsvc_cfg.provider.ip.remote_ip,
+								     nsvc_cfg.provider.ip.remote_udp_port,
+								     1, 1) };
+		rx := f_ns_exp(tr_SNS_ADD(g_nsconfig.nsei, ?, v4 := v4_elem), 0);
+	} else {
+		var template (omit) IP6_Elements v6_elem := { ts_SNS_IPv6(nsvc_cfg.provider.ip.remote_ip,
+								     nsvc_cfg.provider.ip.remote_udp_port,
+								     1, 1) };
+		rx := f_ns_exp(tr_SNS_ADD(g_nsconfig.nsei, ?, omit, v6_elem), 0);
+	}
+
+	/* delete the endpoint */
+	f_vty_config2(NSVTY, {"ns", "bind udp local2"}, "ip-sns signalling-weight 99 data-weight 99");
+	f_vty_config2(NSVTY, {"ns", "nse " & int2str(g_nsconfig.nsei)}, "no ip-sns-bind local2");
+
+	/* accept the SNS_ADD */
+	NSCP[0].send(ts_SNS_ACK(g_nsconfig.nsei, rx.pDU_SNS_Add.transactionID));
+
+	f_incoming_sns_chg_weight(idx_chg := 1);
+	f_incoming_sns_del(idx_del := 1, w_sig := 99, w_user := 99);
+	setverdict(pass);
+	f_clean_ns_codec();
+}
+
 control {
 	if (mp_dialect == NS2_DIALECT_STATIC_RESETBLOCK or mp_dialect == NS2_DIALECT_IPACCESS) {
 		execute( TC_tx_reset() );
@@ -812,6 +858,7 @@
 			execute( TC_sns_sgsn_config_success() );
 			execute( TC_sns_sgsn_add() );
 			execute( TC_sns_sgsn_del() );
+			execute( TC_sns_sgsn_add_change_del() );
 		}
 	}
 }