diff --git a/src/renderer/src/lib/pane-manager/mobile-fit-overrides.test.ts b/src/renderer/src/lib/pane-manager/mobile-fit-overrides.test.ts
index a284b6b19b1..66a4cf4cf28 100644
--- a/src/renderer/src/lib/pane-manager/mobile-fit-overrides.test.ts
+++ b/src/renderer/src/lib/pane-manager/mobile-fit-overrides.test.ts
@@ -301,3 +301,109 @@ describe('getAllOverrides', () => {
     expect(getFitOverrideForPty('pty-1')).not.toBeNull()
   })
 })
+
+// ---------------------------------------------------------------------------
+// Scenario tests (from design doc verification matrix)
+// ---------------------------------------------------------------------------
+
+describe('scenario: desktop window resize while mobile is viewing', () => {
+  it('override persists across setFitOverride calls — desktop safeFit will see it', () => {
+    setFitOverride('pty-1', 'mobile-fit', 49, 20)
+    bindPanePtyId(1, 'pty-1', 'tab-0')
+
+    // Simulate desktop resize triggering a re-check — override should still be there
+    expect(getFitOverrideForPty('pty-1')).toEqual({ mode: 'mobile-fit', cols: 49, rows: 20 })
+    expect(getFitOverrideForPane(1, 'tab-0')).toEqual({ mode: 'mobile-fit', cols: 49, rows: 20 })
+  })
+})
+
+describe('scenario: mobile disconnect restores all terminals', () => {
+  it('clearing all overrides for a disconnected client removes all traces', () => {
+    setFitOverride('pty-1', 'mobile-fit', 49, 20)
+    setFitOverride('pty-2', 'mobile-fit', 49, 20)
+    bindPanePtyId(1, 'pty-1', 'tab-0')
+    bindPanePtyId(2, 'pty-2', 'tab-0')
+
+    // Simulate runtime clearing overrides on disconnect
+    setFitOverride('pty-1', 'desktop-fit', 120, 40)
+    setFitOverride('pty-2', 'desktop-fit', 120, 40)
+
+    expect(getFitOverrideForPty('pty-1')).toBeNull()
+    expect(getFitOverrideForPty('pty-2')).toBeNull()
+    expect(getFitOverrideForPane(1, 'tab-0')).toBeNull()
+    expect(getFitOverrideForPane(2, 'tab-0')).toBeNull()
+  })
+})
+
+describe('scenario: PTY exits while phone-fitted', () => {
+  it('clearing override for exited PTY leaves no stale state', () => {
+    setFitOverride('pty-1', 'mobile-fit', 49, 20)
+    bindPanePtyId(1, 'pty-1', 'tab-0')
+
+    // Runtime clears override on PTY exit
+    setFitOverride('pty-1', 'desktop-fit', 0, 0)
+    unbindPane(1, 'tab-0')
+
+    expect(getFitOverrideForPty('pty-1')).toBeNull()
+    expect(getFitOverrideForPane(1, 'tab-0')).toBeNull()
+    expect(getPaneIdsForPty('pty-1')).toEqual([])
+    expect(getAllOverrides().size).toBe(0)
+  })
+})
+
+describe('scenario: mobile reconnects after disconnect', () => {
+  it('new override after clear works correctly', () => {
+    // First session
+    setFitOverride('pty-1', 'mobile-fit', 49, 20)
+    bindPanePtyId(1, 'pty-1', 'tab-0')
+
+    // Disconnect
+    setFitOverride('pty-1', 'desktop-fit', 120, 40)
+
+    // Reconnect — new session sets override again
+    setFitOverride('pty-1', 'mobile-fit', 55, 22)
+
+    expect(getFitOverrideForPty('pty-1')).toEqual({ mode: 'mobile-fit', cols: 55, rows: 22 })
+    expect(getFitOverrideForPane(1, 'tab-0')).toEqual({ mode: 'mobile-fit', cols: 55, rows: 22 })
+  })
+})
+
+describe('scenario: multiple tabs with same pane IDs', () => {
+  it('override on one tab does not affect the other', () => {
+    bindPanePtyId(1, 'pty-A', 'tab-0')
+    bindPanePtyId(1, 'pty-B', 'tab-1')
+
+    setFitOverride('pty-A', 'mobile-fit', 49, 20)
+
+    expect(getFitOverrideForPane(1, 'tab-0')?.cols).toBe(49)
+    expect(getFitOverrideForPane(1, 'tab-1')).toBeNull()
+  })
+
+  it('clearing override for one tab does not affect the other', () => {
+    bindPanePtyId(1, 'pty-A', 'tab-0')
+    bindPanePtyId(1, 'pty-B', 'tab-1')
+
+    setFitOverride('pty-A', 'mobile-fit', 49, 20)
+    setFitOverride('pty-B', 'mobile-fit', 60, 25)
+
+    // Clear only tab-0's PTY
+    setFitOverride('pty-A', 'desktop-fit', 120, 40)
+
+    expect(getFitOverrideForPane(1, 'tab-0')).toBeNull()
+    expect(getFitOverrideForPane(1, 'tab-1')?.cols).toBe(60)
+  })
+})
+
+describe('scenario: change listener fires for both override and restore', () => {
+  it('tracks full lifecycle: mobile-fit → desktop-fit', () => {
+    const events: { mode: string }[] = []
+    const unsub = onOverrideChange((e) => events.push({ mode: e.mode }))
+
+    setFitOverride('pty-1', 'mobile-fit', 49, 20)
+    setFitOverride('pty-1', 'desktop-fit', 120, 40)
+
+    expect(events).toEqual([{ mode: 'mobile-fit' }, { mode: 'desktop-fit' }])
+
+    unsub()
+  })
+})