diff --git a/bmspy/ups.py b/bmspy/ups.py
index cea9ba0..9033bed 100644
--- a/bmspy/ups.py
+++ b/bmspy/ups.py
@@ -1,7 +1,6 @@
 import argparse
 import atexit
 import os
-import re
 import time
 import smtplib
 import ssl
@@ -65,11 +64,13 @@ def handle_shutdown(action: str = "cancel", delay: int = 0, debug: int = 0) -> N
 
     if action == "shutdown":
         if scheduled_shutdown is False:
-            scheduled_shutdown = time.time() + delay * 60 * 1000
+            scheduled_shutdown = time.time() + delay * 60
             os.system("/sbin/shutdown {}".format(delay))
 
     elif action == "cancel":
         os.system("/sbin/shutdown -c")
+        # Allow the next incident to schedule a shutdown again.
+        scheduled_shutdown = False
 
     return
 
@@ -88,7 +89,7 @@ def handle_email(
     isSSL = False
     hostname = socket.gethostname()
 
-    if re.match("/@/", recipient) is None:
+    if "@" not in recipient:
         recipient = "{}@{}".format(recipient, hostname)
     sender = "bmspy on {} <nobody@{}>".format(hostname, hostname)
 
@@ -169,6 +170,7 @@ def main() -> None:
         "-p",
         dest="port",
         action="store",
+        type=int,
         default=25,
         help="Mail server port (default: 25)",
     )
@@ -229,7 +231,7 @@ def main() -> None:
 
     history = deque()
     while True:
-        data = client.read_data(args.socket, "ups", device=device_name)
+        data = client.read_data(args.socket, "ups", ups=device_name)
         device_obj = data.get(device_name)
         if device_obj is None:
             time.sleep(DAEMON_UPDATE_PERIOD)
diff --git a/tests/test_ups.py b/tests/test_ups.py
index 7cbfb25..be39147 100644
--- a/tests/test_ups.py
+++ b/tests/test_ups.py
@@ -110,6 +110,16 @@ class TestHandleShutdown:
             handle_shutdown(action="cancel")
         assert ups_mod.scheduled_shutdown is False
 
+    def test_second_incident_after_cancel_schedules_again(self):
+        with patch("bmspy.ups.os.system") as mock_sys:
+            handle_shutdown(action="shutdown", delay=5)
+            handle_shutdown(action="cancel")
+            assert ups_mod.scheduled_shutdown is False
+            handle_shutdown(action="shutdown", delay=5)
+        assert [call.args[0] for call in mock_sys.call_args_list] == [
+            "/sbin/shutdown 5", "/sbin/shutdown -c", "/sbin/shutdown 5",
+        ]
+
 
 # ---------------------------------------------------------------------------
 # handle_email
@@ -203,6 +213,13 @@ class TestHandleEmail:
         args = mock_server.sendmail.call_args[0]
         assert args[1] == "root@myhost"
 
+    def test_full_address_is_not_changed(self):
+        mock_smtp_class, mock_server = self._mock_smtp()
+        with patch("bmspy.ups.smtplib.SMTP", mock_smtp_class), \
+             patch("bmspy.ups.socket.gethostname", return_value="myhost"):
+            handle_email(text="test", level="Alert", recipient="user@example.com")
+        assert mock_server.sendmail.call_args[0][1] == "user@example.com"
+
 
 # ---------------------------------------------------------------------------
 # _resolve_ups_device
@@ -370,6 +387,23 @@ class TestUpsMain:
                     ups_mod.main()
         mock_email.assert_called()
 
+    def test_main_mail_port_option_is_a_number(self):
+        """A text port never equals 587, so the STARTTLS check would not match."""
+        ups_mod.warning_sent = False
+        data_seq = [self._make_data(0.0, 0.60)] * 5
+        mock_smtp = MagicMock()
+        server = mock_smtp.return_value.__enter__.return_value
+        with patch("sys.argv", ["bmspy-ups", "--port", "587"]):
+            with pytest.raises(StopIteration):
+                with patch("bmspy.ups.client.read_data", side_effect=[data_seq[0]] + data_seq + [StopIteration("done")]), \
+                     patch("bmspy.ups.client.handle_registration"), \
+                     patch("bmspy.ups.time.sleep"), \
+                     patch("bmspy.ups.handle_shutdown"), \
+                     patch("bmspy.ups.smtplib.SMTP", mock_smtp):
+                    ups_mod.main()
+        mock_smtp.assert_called_with("localhost", 587)
+        server.starttls.assert_called()
+
     def test_main_discharge_alert(self):
         """When current goes negative, discharge alert should be sent.
 
@@ -570,6 +604,21 @@ class TestUpsMainDeviceSelection:
                      patch("bmspy.ups.handle_email"):
                     ups_mod.main()
 
+    def test_main_loop_calls_read_data_with_its_real_parameters(self):
+        """The loop must use the client's parameter names, not only a mock's."""
+        from unittest.mock import create_autospec
+
+        read_data = create_autospec(
+            ups_mod.client.read_data,
+            side_effect=[{"testups": _make_ups(0.0, 0.9)}, StopIteration("done")],
+        )
+        with patch("sys.argv", ["bmspy-ups", "--socket", "/tmp/test.sock"]), \
+             patch("bmspy.ups.client.read_data", read_data), \
+             patch("bmspy.ups.client.handle_registration"):
+            with pytest.raises(StopIteration):
+                ups_mod.main()
+        assert read_data.call_args_list[1] == (("/tmp/test.sock", "ups"), {"ups": "testups"})
+
     def test_main_ups_flag_unknown_device_returns_early(self, capsys):
         """--device with an unknown device name exits with an error."""
         with patch("sys.argv", ["bmspy-ups", "--device", "ghost"]), \