diff --git a/tests/caldav_test_servers.yaml.example b/tests/caldav_test_servers.yaml.example
index 0fbd8e69..cb68b379 100644
--- a/tests/caldav_test_servers.yaml.example
+++ b/tests/caldav_test_servers.yaml.example
@@ -59,18 +59,19 @@ test-servers:
     enabled: ${TEST_CYRUS:-false}
     host: ${CYRUS_HOST:-localhost}
     port: ${CYRUS_PORT:-8802}
-    username: ${CYRUS_USERNAME:-testuser@test.local}
-    password: ${CYRUS_PASSWORD:-testpassword}
+    username: ${CYRUS_USERNAME:-user1}
+    password: ${CYRUS_PASSWORD:-x}
     # Cyrus pre-creates user1-user5 (password 'x'), enabling scheduling tests.
+    # Use plain usernames (no domain): virtdomains is off in the test image.
     scheduling_users:
       - url: http://${CYRUS_HOST:-localhost}:${CYRUS_PORT:-8802}/dav/calendars/user/user1
-        username: user1@test.local
+        username: user1
         password: x
       - url: http://${CYRUS_HOST:-localhost}:${CYRUS_PORT:-8802}/dav/calendars/user/user2
-        username: user2@test.local
+        username: user2
         password: x
       - url: http://${CYRUS_HOST:-localhost}:${CYRUS_PORT:-8802}/dav/calendars/user/user3
-        username: user3@test.local
+        username: user3
         password: x
 
   sogo:
diff --git a/tests/docker-test-servers/cyrus/setup_cyrus.sh b/tests/docker-test-servers/cyrus/setup_cyrus.sh
index f317e20e..de862082 100755
--- a/tests/docker-test-servers/cyrus/setup_cyrus.sh
+++ b/tests/docker-test-servers/cyrus/setup_cyrus.sh
@@ -41,6 +41,18 @@ for i in $(seq 1 $max_caldav_attempts); do
     sleep 2
 done
 
+echo ""
+echo "Granting scheduling ACL rights to pre-provisioned users..."
+# Cyrus 3.13.x pre-creates user1's calendar home in the Docker image without
+# the extended scheduling rights (7=schedule-send-invite, 8=schedule-send-reply,
+# 9=schedule-send-freebusy).  Dynamically-created calendar homes (user2+) get
+# these rights automatically, so we only need to patch user1 here, but grant
+# to all known pre-created users for safety.
+for user in user1 user2 user3 user4 user5; do
+    printf 'sam user.%s.#calendars.Outbox %s lrswipkxtecdan789\r\n' "$user" "$user"
+done | /usr/cyrus/bin/cyradm --auth PLAIN -u admin -w admin --notls --port 8143 localhost 2>/dev/null || \
+    echo "Warning: could not set scheduling ACL rights (cyradm failed)"
+
 echo ""
 echo "✓ Cyrus setup complete!"
 echo ""