diff --git a/services/platform-service/src/modules/support-cases/routes.test.ts b/services/platform-service/src/modules/support-cases/routes.test.ts
index f3ccc5c3..048e6653 100644
--- a/services/platform-service/src/modules/support-cases/routes.test.ts
+++ b/services/platform-service/src/modules/support-cases/routes.test.ts
@@ -225,6 +225,36 @@ describe('supportCaseRoutes', () => {
     expect(body.tagsAdded).toContain('category:billing');
   });
 
+  it('POST /support/cases/:id/auto-triage does not regress status of in-progress cases', async () => {
+    repoMock.getCase.mockResolvedValue({
+      id: 'sup_4',
+      productId: 'lysnrai',
+      title: 'Error on login page',
+      description: 'Users see 500',
+      priority: 'medium',
+      status: 'in_progress',
+      tags: [],
+    });
+    repoMock.updateCase.mockImplementation(
+      async (_id: string, _pid: string, updates: Record<string, unknown>) => ({
+        ...updates,
+        id: 'sup_4',
+      })
+    );
+    const app = await buildApp({ sub: 'admin_1', productId: 'lysnrai', role: 'admin' });
+
+    const res = await app.inject({ method: 'POST', url: '/api/support/cases/sup_4/auto-triage' });
+    expect(res.statusCode).toBe(200);
+    const body = res.json();
+    expect(body.newPriority).toBe('high');
+    // Status should remain in_progress, not regress to triaged
+    expect(repoMock.updateCase).toHaveBeenCalledWith(
+      'sup_4',
+      'lysnrai',
+      expect.objectContaining({ status: 'in_progress' })
+    );
+  });
+
   it('POST /support/cases/:id/auto-triage handles undefined tags gracefully', async () => {
     repoMock.getCase.mockResolvedValue({
       id: 'sup_3',
diff --git a/services/platform-service/src/modules/support-cases/routes.ts b/services/platform-service/src/modules/support-cases/routes.ts
index a7f9e647..a02a7fed 100644
--- a/services/platform-service/src/modules/support-cases/routes.ts
+++ b/services/platform-service/src/modules/support-cases/routes.ts
@@ -283,9 +283,14 @@ export async function supportCaseRoutes(app: FastifyInstance) {
     }
 
     const dedupedTags = [...new Set(tags)];
+    // Only advance to 'triaged' if still in 'open' state — don't regress later statuses
+    const triageableStatuses = ['open'];
+    const statusUpdate = triageableStatuses.includes(supportCase.status)
+      ? 'triaged'
+      : supportCase.status;
     const updated = await repo.updateCase(id, access.productId, {
       priority: suggestedPriority as SupportCaseDoc['priority'],
-      status: 'triaged',
+      status: statusUpdate,
       tags: dedupedTags,
     });