diff --git a/tests/test_nat_detection.c b/tests/test_nat_detection.c
index f6e2d585..ad214325 100644
--- a/tests/test_nat_detection.c
+++ b/tests/test_nat_detection.c
@@ -126,7 +126,7 @@ static void test_all_groups_tcp(void) {
     nat_detection_connection_failed(owner->nat_det, failed, 0);
     assert(!nat_detection_get_status(owner->nat_det, socket, &status) && status.round == verified_round);
     nat_detection_connection_failed(owner->nat_det, failed, 1);
-    end = get_time_tb() + 50000;
+    end = get_time_tb() + 400000;
     do { uasync_poll(fixture.ua, 10); assert(!nat_detection_get_status(owner->nat_det, socket, &status)); }
     while (get_time_tb() < end && (status.round == verified_round || status.phase || status.cycling));
     assert(status.round != verified_round && !status.phase && !status.cycling);
diff --git a/tests/test_stun_nat.c b/tests/test_stun_nat.c
index 587526c9..96764ab4 100644
--- a/tests/test_stun_nat.c
+++ b/tests/test_stun_nat.c
@@ -371,8 +371,7 @@ static void wait_source(struct nat_fixture* nf, struct ETCP_SOCKET* socket, uint
     abort();
 }
 
-/* Настоящее ядро: нет узлов -> один наблюдатель -> независимый третий узел.
- * Сервер сообщает translated EIM, реальный рабочий loopback endpoint — UNCHANGED. */
+/* STUN другого порта не назначает профиль рабочему endpoint, даже без ETCP-наблюдателей. */
 static void test_fallback(void) {
     struct nat_fixture nf; nat_fixture_init(&nf);
     struct fixture server = {.ua = nf.ua, .rfc = 1, .mapping = STUN_MAP_EIM,
@@ -384,22 +383,26 @@ static void test_fallback(void) {
     struct UTUN_INSTANCE* owner = nat_fixture_node(&nf, "127.0.0.1", NULL, config);
     struct ETCP_SOCKET* socket = test_etcp_bound_socket(owner, "udp");
     struct ETCP_SOCKET* duplicate = test_etcp_bound_socket(owner, "duplicate");
-    wait_source(&nf, socket, ADDRESS_SOURCE_STUN); wait_source(&nf, duplicate, ADDRESS_SOURCE_STUN);
-    assert(socket->address_profile.mapping == ADDRESS_MAP_EIM && socket->address_profile.inbound == ADDRESS_IN_OPEN);
+    struct stun_nat_result diagnostic;
+    uint64_t end = get_time_tb() + 3000000;
+    do { test_clock_poll(nf.ua, 10000); assert(!stun_nat_get_socket_result(owner, socket, &diagnostic)); }
+    while (get_time_tb() < end && diagnostic.status == STUN_NAT_PENDING);
+    assert(diagnostic.mapping == STUN_MAP_EIM && diagnostic.filtering == STUN_FILTER_EIF);
+    assert(socket->address_profile.source == ADDRESS_SOURCE_NONE && !socket->address_profile.mapping && !socket->address_profile.inbound);
     assert(!memcmp(&socket->address_profile, &duplicate->address_profile, sizeof(socket->address_profile)));
     assert(!socket->nat_addr.ss_family && !duplicate->nat_addr.ss_family);
     struct nat_check_status status; assert(!nat_detection_get_status(owner->nat_det, socket, &status));
-    assert(status.reason == NAT_REASON_NO_OBSERVER && status.fallback_allowed);
+    assert(status.reason == NAT_REASON_NO_OBSERVER);
     struct TOPO_NODE* snapshot = topo_node_registry_find(owner->topo_groups, owner->node_id);
     assert(snapshot && !topo_node_verify(snapshot));
     for (const struct TOPO_ADDR4* address = snapshot->v4_addrs; address; address = address->next)
         assert(address->type != TOPO_ADDR_NAT); /* тестовый внешний порт не опубликован */
     struct UTUN_INSTANCE* observer = nat_fixture_node(&nf, "127.0.0.5", NULL, NULL);
     nat_fixture_connect(&nf, owner, "udp", observer); nat_detection_request_check_all(owner->nat_det);
-    uint64_t end = get_time_tb() + 300000;
+    end = get_time_tb() + 300000;
     do { test_clock_poll(nf.ua, 10000); nat_detection_get_status(owner->nat_det, socket, &status); }
     while (get_time_tb() < end && status.reason != NAT_REASON_NO_HELPER);
-    assert(status.reason == NAT_REASON_NO_HELPER && socket->address_profile.source == ADDRESS_SOURCE_STUN);
+    assert(status.reason == NAT_REASON_NO_HELPER && socket->address_profile.source == ADDRESS_SOURCE_NONE);
     struct UTUN_INSTANCE* helper = nat_fixture_node(&nf, "127.0.0.6", NULL, NULL);
     nat_fixture_connect(&nf, observer, "udp", helper); nat_detection_request_check_all(owner->nat_det);
     wait_source(&nf, socket, ADDRESS_SOURCE_ETCP); wait_source(&nf, duplicate, ADDRESS_SOURCE_ETCP);
@@ -427,7 +430,7 @@ static void test_fallback(void) {
         assert(!uasync_remove_socket_t(nf.ua, server.endpoints[i].fd)); socket_close_wrapper(server.endpoints[i].fd);
     }
     socket_close_wrapper(server.source.fd); nat_fixture_cleanup(&nf);
-    DEBUG_INFO(DEBUG_CATEGORY_NAT, "PASS STUN fallback: no peers, no independent helper, ETCP priority, unchanged real endpoint");
+    DEBUG_INFO(DEBUG_CATEGORY_NAT, "PASS STUN isolation: diagnostics never replace the measured working endpoint");
 }
 
 int main(void) {