diff --git a/SeaHavenIndustries.Tests/WorkOrderOverdueTypeTests.cs b/SeaHavenIndustries.Tests/WorkOrderOverdueTypeTests.cs
index 35c04e6..7a1ee1e 100644
--- a/SeaHavenIndustries.Tests/WorkOrderOverdueTypeTests.cs
+++ b/SeaHavenIndustries.Tests/WorkOrderOverdueTypeTests.cs
@@ -183,6 +183,47 @@ public class WorkOrderOverdueTypeTests
         Assert.Null(persisted.Severity);
     }
 
+    // The board sends one request per field, severity before type, so correcting
+    // Overdue to Emergency patches severity while the stored type is still Overdue.
+    // A severity patch must not be dropped or rejected for the current type; the
+    // no-severity invariant is enforced when the type itself changes.
+    [Fact]
+    public async Task PatchSeverityThenType_OverdueToEmergency_KeepsSeverity()
+    {
+        await using var context = NewContext();
+        var wo = new WorkOrder
+        {
+            Id = 1,
+            LifecycleStatus = LifecycleStatus.Scheduled,
+            WorkOrderType = WorkOrderType.Overdue,
+            RowVersion = new byte[] { 1, 0, 0, 0, 0, 0, 0, 1 }
+        };
+        context.workOrders.Add(wo);
+        await context.SaveChangesAsync();
+        var service = NewUpdateService(context);
+
+        await service.PatchFieldAsync(1, new WorkOrderBoardPatchRequestDto
+        {
+            Field = WorkOrderBoardFieldNames.Severity,
+            Value = "2",
+            WorkOrderVersion = ToVersion(wo)
+        }, "actor-1");
+
+        var updated = await context.workOrders.SingleAsync(w => w.Id == 1);
+        var result = await service.PatchFieldAsync(1, new WorkOrderBoardPatchRequestDto
+        {
+            Field = WorkOrderBoardFieldNames.WorkOrderType,
+            Value = "Emergency",
+            WorkOrderVersion = ToVersion(updated)
+        }, "actor-1");
+
+        Assert.Equal(WorkOrderType.Emergency, result.WorkOrderType);
+        Assert.Equal(2, result.Severity);
+        var persisted = await context.workOrders.SingleAsync(w => w.Id == 1);
+        Assert.Equal(WorkOrderType.Emergency, persisted.WorkOrderType);
+        Assert.Equal("2", persisted.Severity);
+    }
+
     [Fact]
     public async Task PatchType_PmWithPmService_ToOverdue_KeepsService()
     {