diff --git a/src/Nonemm.Session/ContestSession.cs b/src/Nonemm.Session/ContestSession.cs
index f42d40f..9f8e4dd 100644
--- a/src/Nonemm.Session/ContestSession.cs
+++ b/src/Nonemm.Session/ContestSession.cs
@@ -111,7 +111,7 @@ public sealed class ContestSession
         {
             Log.Replace(stored);
         }
-        Numbers.Record(stored.SentNumber, stored.Band);
+        RecordNumber(stored);
         Logged?.Invoke(this, stored);
         Changed?.Invoke(this, EventArgs.Empty);
         return stored;
@@ -203,7 +203,7 @@ public sealed class ContestSession
         }
         Qso arrived = store.Add(FromNetwork(qso));
         Log.Insert(arrived);
-        Numbers.Record(arrived.SentNumber, arrived.Band);
+        RecordNumber(arrived);
         Changed?.Invoke(this, EventArgs.Empty);
         return true;
     }
@@ -274,6 +274,19 @@ public sealed class ContestSession
             ? Log.Qsos.Where(q =>
                 Contest.SessionOf(q.TimestampUtc) == Contest.SessionOf(DateTime.UtcNow))
             : Log.Qsos;
-        Numbers.SeedFrom(counted);
+        Numbers.SeedFrom(counted.Where(Contest.IsContact));
+    }
+
+    /// The sent number of a contact, and nothing else. A WAE QTC row carries
+    /// the serial of the contact it reports in the same column, and that
+    /// number was sent by the station being reported rather than by us, so
+    /// taking it would push our own numbers up. N1MM leaves the QTC rows out
+    /// of the same query, in `QSONrsByBand`.
+    private void RecordNumber(Qso qso)
+    {
+        if (Contest.IsContact(qso))
+        {
+            Numbers.Record(qso.SentNumber, qso.Band);
+        }
     }
 }
diff --git a/tests/Nonemm.Session.Tests/QtcRestartTests.cs b/tests/Nonemm.Session.Tests/QtcRestartTests.cs
new file mode 100644
index 0000000..95ac535
--- /dev/null
+++ b/tests/Nonemm.Session.Tests/QtcRestartTests.cs
@@ -0,0 +1,138 @@
+using Microsoft.Data.Sqlite;
+using Nonemm.Contests;
+using Nonemm.Contests.Rules;
+using Nonemm.Core;
+using Nonemm.Core.Country;
+using Nonemm.Storage;
+
+namespace Nonemm.Session.Tests;
+
+/// QTC traffic through a real log file and back: what a station has already
+/// had, which contacts have already been reported and how the series are
+/// numbered all come from the log rows, so they have to survive the program
+/// being closed and opened again.
+public class QtcRestartTests : IDisposable
+{
+    private const string Countries = """
+        Germany:                  14:  28:  EU:   51.00:  -10.00:   -1.0:  DL:
+            DL,DK,DJ;
+        United States:            05:  08:  NA:   37.53:   91.67:    5.0:  K:
+            K,W,N,AA,NE;
+        """;
+
+    private static readonly StationInfo UnitedStates = new()
+    {
+        Callsign = "NE1C",
+        CqZone = 5,
+        ItuZone = 8,
+        Continent = "NA",
+        CountryPrefix = "K",
+    };
+
+    private readonly string path = Path.Combine(Path.GetTempPath(), $"nonemm-{Guid.NewGuid():N}.s3db");
+
+    public void Dispose()
+    {
+        SqliteConnection.ClearAllPools();
+        File.Delete(path);
+        GC.SuppressFinalize(this);
+    }
+
+    /// Opens the log the way the program does when it starts: the store, then
+    /// the contest, then the position.
+    private OperatingPosition Open()
+    {
+        SqliteLogStore store = SqliteLogStore.Open(path);
+        ContestInstance instance = store.Contest(1) ?? store.AddContest(new ContestInstance
+        {
+            ContestNumber = 0,
+            ContestName = "WAECW",
+            ModeCategory = "CW",
+        });
+        return new OperatingPosition(new ContestSession(
+            store,
+            new Wae(ModeCategory.Cw),
+            instance,
+            UnitedStates,
+            CountryFile.Parse(Countries)));
+    }
+
+    private static Qso Contact(
+        OperatingPosition position,
+        string call,
+        int receivedNumber,
+        int minute) =>
+        position.Session.Add(new Qso
+        {
+            Id = Qso.NewId(),
+            TimestampUtc = new DateTime(2026, 11, 14, 13, minute, 0, DateTimeKind.Utc),
+            Call = Callsign.Parse(call),
+            Frequency = Frequency.FromKilohertz(14_025),
+            Mode = Modes.Cw,
+            ContestName = "WAECW",
+            ContestNumber = position.Instance.ContestNumber,
+            SentReport = "599",
+            ReceivedReport = "599",
+            SentNumber = position.Session.ReserveNumberOn(position.Band),
+            ReceivedNumber = receivedNumber,
+            Exchange1 = WaeQtc.Contact,
+        });
+
+    private static void Send(OperatingPosition position, IReadOnlyList<WaeQtc> lines)
+    {
+        for (int line = 0; line < lines.Count; line++)
+        {
+            position.Session.Add(lines[line].ApplyTo(new Qso
+            {
+                Id = Qso.NewId(),
+                TimestampUtc = new DateTime(2026, 11, 14, 14, 0, line, DateTimeKind.Utc),
+                Call = lines[line].Station,
+                Frequency = Frequency.FromKilohertz(14_025),
+                Mode = Modes.Cw,
+                ContestName = "WAECW",
+                ContestNumber = position.Instance.ContestNumber,
+            }));
+        }
+    }
+
+    [Fact]
+    public void TheSeriesCarriesOnAfterTheProgramIsOpenedAgain()
+    {
+        OperatingPosition first = Open();
+        QtcTraffic traffic = new(first);
+        Contact(first, "DL1AAA", receivedNumber: 16, minute: 40);
+        Contact(first, "DL2BBB", receivedNumber: 40, minute: 41);
+        Contact(first, "DL3CCC", receivedNumber: 7, minute: 42);
+        Send(first, traffic.ToSend(Callsign.Parse("DL9XYZ"), mostPerSeries: 2));
+        Assert.Equal(2, traffic.NextSeries());
+
+        OperatingPosition second = Open();
+        QtcTraffic reopened = new(second);
+
+        // the series number carries on rather than starting at one again
+        Assert.Equal(2, reopened.NextSeries());
+        // and the two contacts already reported are not offered a second time
+        Assert.Equal(
+            ["DL3CCC"],
+            reopened.ToSend(Callsign.Parse("DL9XYZ")).Select(l => l.Call.Text).ToList());
+        QtcCounts counts = reopened.CountsFor(Callsign.Parse("DL9XYZ"));
+        Assert.Equal(2, counts.Exchanged);
+        Assert.Equal(1, counts.Available);
+        Assert.Equal(1, counts.LeftWith);
+    }
+
+    /// A QTC row holds the serial of the contact it reports, which the other
+    /// station sent. Taking that for our own next number would jump the log
+    /// forward; N1MM leaves the QTC rows out of the same query.
+    [Fact]
+    public void TrafficDoesNotTakeTheNextSerialNumber()
+    {
+        OperatingPosition first = Open();
+        Contact(first, "DL1AAA", receivedNumber: 1_450, minute: 40);
+        Contact(first, "DL2BBB", receivedNumber: 1_800, minute: 41);
+        Send(first, new QtcTraffic(first).ToSend(Callsign.Parse("DL9XYZ")));
+
+        Assert.Equal(3, first.SentNumber);
+        Assert.Equal(3, Open().SentNumber);
+    }
+}