diff --git a/src/LogExpert.Core/Classes/Log/LogfileReader.cs b/src/LogExpert.Core/Classes/Log/LogfileReader.cs
index 9e2495d9..e520102a 100644
--- a/src/LogExpert.Core/Classes/Log/LogfileReader.cs
+++ b/src/LogExpert.Core/Classes/Log/LogfileReader.cs
@@ -150,7 +150,7 @@ private LogfileReader (
 
         ILogFileInfo fileInfo = null;
 
-        IsMultiFile = multiFile || fileNames.Length == 1;
+        IsMultiFile = multiFile;
         _fileName = fileNames[0];
 
         IEnumerable<string> names = IsMultiFile
@@ -1964,4 +1964,4 @@ PinHandle IBufferPinning.PinRange (int startLine, int endLine)
     }
 
     #endregion
-}
\ No newline at end of file
+}
diff --git a/src/LogExpert.Tests/LogExpert.Tests.csproj b/src/LogExpert.Tests/LogExpert.Tests.csproj
index d8bfb785..6747becb 100644
--- a/src/LogExpert.Tests/LogExpert.Tests.csproj
+++ b/src/LogExpert.Tests/LogExpert.Tests.csproj
@@ -101,10 +101,16 @@
     <Content Include="TestData\tab.csv">
       <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
     </Content>
-    <Content Include="TestData\comma.csv">
-      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
-    </Content>
-    <None Update="TestData\organizations-1000.csv">
+    <Content Include="TestData\comma.csv">
+      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
+    </Content>
+    <Content Include="TestData\app.log">
+      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
+    </Content>
+    <Content Include="TestData\app.log.1">
+      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
+    </Content>
+    <None Update="TestData\organizations-1000.csv">
       <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
     </None>
     <None Update="TestData\organizations-10000.csv">
diff --git a/src/LogExpert.Tests/StreamReaderTests/LogfileReaderMultiFileFlagTests.cs b/src/LogExpert.Tests/StreamReaderTests/LogfileReaderMultiFileFlagTests.cs
new file mode 100644
index 00000000..5522313d
--- /dev/null
+++ b/src/LogExpert.Tests/StreamReaderTests/LogfileReaderMultiFileFlagTests.cs
@@ -0,0 +1,109 @@
+using System.Text;
+
+using LogExpert.Core.Classes.Log;
+using LogExpert.Core.Classes.Log.ProgressReporters;
+using LogExpert.Core.Entities;
+using LogExpert.Core.Enums;
+
+using NUnit.Framework;
+
+namespace LogExpert.Tests.StreamReaderTests;
+
+[TestFixture]
+internal sealed class LogfileReaderMultiFileFlagTests
+{
+    private static readonly string _testDataDirectory = Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "TestData");
+
+    private string _testDirectory = null!;
+    private string _logFile = null!;
+
+    [SetUp]
+    public void SetUp ()
+    {
+        _testDirectory = Path.Combine(Path.GetTempPath(), "LogExpertTests", Guid.NewGuid().ToString());
+        _ = Directory.CreateDirectory(_testDirectory);
+        _logFile = Path.Combine(_testDirectory, "app.log");
+
+        File.Copy(Path.Combine(_testDataDirectory, "app.log"), _logFile);
+        File.Copy(Path.Combine(_testDataDirectory, "app.log.1"), _logFile + ".1");
+
+        _ = PluginRegistry.PluginRegistry.Create(_testDirectory, 500);
+    }
+
+    [TearDown]
+    public void TearDown ()
+    {
+        if (Directory.Exists(_testDirectory))
+        {
+            Directory.Delete(_testDirectory, recursive: true);
+        }
+    }
+
+    [Test]
+    public void SingleFileCtor_MultiFileFalse_DoesNotExpandRollover ()
+    {
+        using var reader = CreateSingleFileReader(multiFile: false);
+
+        reader.ReadFiles();
+
+        Assert.Multiple(() =>
+        {
+            Assert.That(reader.IsMultiFile, Is.False);
+            Assert.That(reader.GetLogFileInfoList(), Has.Count.EqualTo(1));
+            Assert.That(reader.LineCount, Is.EqualTo(1));
+        });
+    }
+
+    [Test]
+    public void SingleFileCtor_MultiFileTrue_ExpandsRollover ()
+    {
+        using var reader = CreateSingleFileReader(multiFile: true);
+
+        reader.ReadFiles();
+
+        Assert.Multiple(() =>
+        {
+            Assert.That(reader.IsMultiFile, Is.True);
+            Assert.That(reader.GetLogFileInfoList(), Has.Count.EqualTo(2));
+        });
+    }
+
+    [Test]
+    public void MultiFileCtor_AlwaysMultiFile ()
+    {
+        using var reader = new LogfileReader(
+            [_logFile],
+            new EncodingOptions { Encoding = Encoding.UTF8 },
+            bufferCount: 40,
+            linesPerBuffer: 50,
+            new MultiFileOptions(),
+            ReaderType.System,
+            PluginRegistry.PluginRegistry.Instance,
+            maximumLineLength: 500,
+            progressReporter: NullProgressReporter.Instance);
+
+        reader.ReadFiles();
+
+        Assert.Multiple(() =>
+        {
+            Assert.That(reader.IsMultiFile, Is.True);
+            Assert.That(reader.GetLogFileInfoList(), Has.Count.EqualTo(2));
+        });
+    }
+
+    private LogfileReader CreateSingleFileReader (bool multiFile)
+    {
+        return new LogfileReader(
+            _logFile,
+            new EncodingOptions { Encoding = Encoding.UTF8 },
+            multiFile,
+            bufferCount: 40,
+            linesPerBuffer: 50,
+            new MultiFileOptions(),
+            ReaderType.System,
+            PluginRegistry.PluginRegistry.Instance,
+            maximumLineLength: 500,
+            progressReporter: NullProgressReporter.Instance);
+    }
+
+}
diff --git a/src/LogExpert.Tests/StreamReaderTests/LogfileReaderSingleFileMonitoringTests.cs b/src/LogExpert.Tests/StreamReaderTests/LogfileReaderSingleFileMonitoringTests.cs
new file mode 100644
index 00000000..cad47c6c
--- /dev/null
+++ b/src/LogExpert.Tests/StreamReaderTests/LogfileReaderSingleFileMonitoringTests.cs
@@ -0,0 +1,76 @@
+using System.Text;
+
+using LogExpert.Core.Classes.Log;
+using LogExpert.Core.Entities;
+using LogExpert.Core.Enums;
+using LogExpert.Core.Interfaces;
+
+using Moq;
+
+using NUnit.Framework;
+
+namespace LogExpert.Tests.StreamReaderTests;
+
+[TestFixture]
+internal sealed class LogfileReaderSingleFileMonitoringTests
+{
+    private string _testDirectory = null!;
+    private string _logFile = null!;
+
+    [SetUp]
+    public void SetUp ()
+    {
+        _testDirectory = Path.Combine(Path.GetTempPath(), "LogExpertTests", Guid.NewGuid().ToString());
+        _ = Directory.CreateDirectory(_testDirectory);
+        _logFile = Path.Combine(_testDirectory, "app.log");
+        File.WriteAllLines(_logFile, Enumerable.Range(1, 100).Select(index => $"Line {index}"), Encoding.UTF8);
+
+        _ = PluginRegistry.PluginRegistry.Create(_testDirectory, 500);
+    }
+
+    [TearDown]
+    public void TearDown ()
+    {
+        if (Directory.Exists(_testDirectory))
+        {
+            Directory.Delete(_testDirectory, recursive: true);
+        }
+    }
+
+    [Test]
+    public void SingleFileReader_OnTruncation_ReportsNewFileNotRollover ()
+    {
+        using var loadingFinished = new ManualResetEventSlim(false);
+        using var newFileReported = new ManualResetEventSlim(false);
+        var progressReporterMock = new Mock<ILoadProgressReporter>();
+        progressReporterMock
+            .Setup(reporter => reporter.ReportLoadingFinished())
+            .Callback(() => loadingFinished.Set());
+        progressReporterMock
+            .Setup(reporter => reporter.ReportNewFile(It.IsAny<string>(), It.IsAny<long>(), It.IsAny<long>()))
+            .Callback(() => newFileReported.Set());
+
+        using var reader = new LogfileReader(
+            _logFile,
+            new EncodingOptions { Encoding = Encoding.UTF8 },
+            multiFile: false,
+            bufferCount: 40,
+            linesPerBuffer: 50,
+            new MultiFileOptions(),
+            ReaderType.System,
+            PluginRegistry.PluginRegistry.Instance,
+            maximumLineLength: 500,
+            progressReporter: progressReporterMock.Object);
+
+        var rolloverReported = false;
+        reader.FileSizeChanged += (_, args) => rolloverReported |= args.IsRollover;
+
+        reader.StartMonitoring();
+        Assert.That(loadingFinished.Wait(TimeSpan.FromSeconds(5)), Is.True, "Initial load did not finish");
+
+        File.WriteAllText(_logFile, "replacement\n", Encoding.UTF8);
+
+        Assert.That(newFileReported.Wait(TimeSpan.FromSeconds(5)), Is.True, "Truncation did not report a new file");
+        Assert.That(rolloverReported, Is.False);
+    }
+}
diff --git a/src/LogExpert.Tests/TestData/app.log b/src/LogExpert.Tests/TestData/app.log
new file mode 100644
index 00000000..c69b11e7
--- /dev/null
+++ b/src/LogExpert.Tests/TestData/app.log
@@ -0,0 +1 @@
+app.log
\ No newline at end of file
diff --git a/src/LogExpert.Tests/TestData/app.log.1 b/src/LogExpert.Tests/TestData/app.log.1
new file mode 100644
index 00000000..e17d75d3
--- /dev/null
+++ b/src/LogExpert.Tests/TestData/app.log.1
@@ -0,0 +1 @@
+app.log.1
\ No newline at end of file