diff --git a/EDILibrary/EdifactFormatVersion.cs b/EDILibrary/EdifactFormatVersion.cs
index 67c58c7..d8b776e 100644
--- a/EDILibrary/EdifactFormatVersion.cs
+++ b/EDILibrary/EdifactFormatVersion.cs
@@ -355,9 +355,10 @@ public class EdifactFormatVersionHelper : IEdifactFormatVersionProvider
         private static readonly DateTime KeyDate2310 = new(2023, 09, 30, 22, 0, 0, DateTimeKind.Utc);
 
         /// <summary>
-        /// validity date of <see cref="EdifactFormatVersion.FV2310"/>
+        /// validity date of <see cref="EdifactFormatVersion.FV2404"/>
         /// </summary>
-        private static readonly DateTime KeyDate2404 = new(2024, 03, 31, 22, 0, 0, DateTimeKind.Utc);
+        /// <remarks>Note that this is _not_ April 1st</remarks>
+        private static readonly DateTime KeyDate2404 = new(2024, 04, 02, 22, 0, 0, DateTimeKind.Utc);
         public EdifactFormatVersion GetFormatVersion(DateTimeOffset keydate)
         {
             if (keydate >= KeyDate2404)
diff --git a/EDILibraryTests/EdifactFormatVersionTests.cs b/EDILibraryTests/EdifactFormatVersionTests.cs
index 2bd576d..dec719d 100644
--- a/EDILibraryTests/EdifactFormatVersionTests.cs
+++ b/EDILibraryTests/EdifactFormatVersionTests.cs
@@ -157,7 +157,8 @@ public void TestFV2110()
             Assert.AreEqual(EdifactFormatVersion.FV2110, versionProvider.GetFormatVersion(new DateTimeOffset(2022, 9, 30, 21, 59, 59, TimeSpan.Zero)));
             Assert.AreEqual(EdifactFormatVersion.FV2210, versionProvider.GetFormatVersion(new DateTimeOffset(2022, 9, 30, 22, 0, 0, TimeSpan.Zero)));
             Assert.AreEqual(EdifactFormatVersion.FV2310, versionProvider.GetFormatVersion(new DateTimeOffset(2023, 9, 30, 22, 0, 0, TimeSpan.Zero)));
-            Assert.AreEqual(EdifactFormatVersion.FV2404, versionProvider.GetFormatVersion(new DateTimeOffset(2024, 3, 31, 22, 0, 0, TimeSpan.Zero)));
+            Assert.AreEqual(EdifactFormatVersion.FV2310, versionProvider.GetFormatVersion(new DateTimeOffset(2024, 3, 31, 22, 0, 0, TimeSpan.Zero)));
+            Assert.AreEqual(EdifactFormatVersion.FV2404, versionProvider.GetFormatVersion(new DateTimeOffset(2024, 4, 2, 22, 0, 0, TimeSpan.Zero)));
         }
     }
 }