diff --git a/frontend/src/components/common/CalendarWeek.test.tsx b/frontend/src/components/common/CalendarWeek.test.tsx
index 64a5657..05f81a1 100644
--- a/frontend/src/components/common/CalendarWeek.test.tsx
+++ b/frontend/src/components/common/CalendarWeek.test.tsx
@@ -266,6 +266,27 @@ describe('CalendarWeek', () => {
       render(<CalendarWeek {...defaultProps} plannedDays={[]} />)
       expect(screen.queryByTestId('calendar-event')).not.toBeInTheDocument()
     })
+
+    it('composes the band aria-label from parent label, type label, and the interpolated date range', () => {
+      // Regression guard: a tips bug in this repo surfaced as the literal
+      // un-interpolated "Tip: {title}" in an accessibility label and nothing
+      // caught it. Assert the real composed string here, not merely that an
+      // aria-label attribute exists.
+      const plannedDays = [
+        pd({ id: '1', date: '2026-01-05', dayType: 'sjukpenning' }),
+        pd({ id: '2', date: '2026-01-06', dayType: 'sjukpenning' }),
+      ]
+      render(<CalendarWeek {...defaultProps} plannedDays={plannedDays} parentName="Alice" />)
+      const band = screen.getAllByTestId(/^calendar-band-/)[0]
+      expect(band).toHaveAttribute('aria-label', 'Alice · Sjukpenning, 2026-01-05 – 2026-01-06')
+    })
+
+    it('uses the partner label in the band aria-label for the other parent\'s days', () => {
+      const plannedDays = [pd({ id: '1', date: '2026-01-05', parentPersonalDataUuid: 'other-parent' })]
+      render(<CalendarWeek {...defaultProps} plannedDays={plannedDays} personalDataUuid="parent-1" />)
+      const band = screen.getAllByTestId(/^calendar-band-/)[0]
+      expect(band).toHaveAttribute('aria-label', 'Partner · Semester, 2026-01-05 – 2026-01-05')
+    })
   })
 
   describe('the weekend-gap bug: a wish-linked band bridges free-day gaps', () => {
diff --git a/frontend/src/hooks/useDayOverrides.test.ts b/frontend/src/hooks/useDayOverrides.test.ts
index 62f211a..b2e00d8 100644
--- a/frontend/src/hooks/useDayOverrides.test.ts
+++ b/frontend/src/hooks/useDayOverrides.test.ts
@@ -8,24 +8,18 @@ vi.mock('@/services/api')
 
 describe('useDayOverrides', () => {
   const mockOverrides = [
-    {
+    makeDayOverride({
       id: 'do-1',
-      workspaceId: 'ws-1',
       date: '2026-12-24',
       isWorkingDay: true,
       note: 'Jobbade på juldagen',
-      createdAt: '2026-01-01T00:00:00',
-      updatedAt: '2026-01-01T00:00:00',
-    },
-    {
+    }),
+    makeDayOverride({
       id: 'do-2',
-      workspaceId: 'ws-1',
       date: '2026-06-20',
       isWorkingDay: false,
       note: 'Extra ledigt',
-      createdAt: '2026-01-01T00:00:00',
-      updatedAt: '2026-01-01T00:00:00',
-    },
+    }),
   ]
 
   beforeEach(() => {
diff --git a/frontend/src/services/api.test.ts b/frontend/src/services/api.test.ts
index f1cfc20..91923b5 100644
--- a/frontend/src/services/api.test.ts
+++ b/frontend/src/services/api.test.ts
@@ -432,6 +432,74 @@ describe('API response mappers (snake_case → camelCase)', () => {
       expect(result.createdAt).toBe('2026-06-14T17:09:47')
     })
   })
+
+  describe('listDayOverridesByWorkspace', () => {
+    it('maps snake_case day overrides to camelCase', async () => {
+      // Regression test: toDayOverride was the only mapper in this file with
+      // no snake_case→camelCase test — this is the exact shape of bug that
+      // shipped for getTips (see the getTips test below): a missing/wrong
+      // mapping surfaces only at runtime, never in a suite that mocks the
+      // module and hand-rolls already-camelCase fixtures.
+      const rawResponse = [
+        {
+          id: 'do-1',
+          workspace_id: 'ws1',
+          date: '2026-12-24',
+          is_working_day: true,
+          note: 'Jobbade på juldagen',
+          created_at: '2026-01-01T00:00:00',
+          updated_at: '2026-01-02T00:00:00',
+        },
+      ]
+
+      fetchMock.mockResolvedValue({
+        ok: true,
+        status: 200,
+        json: async () => rawResponse,
+      })
+
+      const result = await api.listDayOverridesByWorkspace('ws1')
+
+      expect(result).toEqual([
+        {
+          id: 'do-1',
+          workspaceId: 'ws1',
+          date: '2026-12-24',
+          isWorkingDay: true,
+          note: 'Jobbade på juldagen',
+          createdAt: '2026-01-01T00:00:00',
+          updatedAt: '2026-01-02T00:00:00',
+        },
+      ])
+    })
+
+    it('maps a null note/created_at/updated_at through unchanged', async () => {
+      const rawResponse = [
+        {
+          id: 'do-2',
+          workspace_id: 'ws1',
+          date: '2026-06-20',
+          is_working_day: false,
+          note: null,
+          created_at: null,
+          updated_at: null,
+        },
+      ]
+
+      fetchMock.mockResolvedValue({
+        ok: true,
+        status: 200,
+        json: async () => rawResponse,
+      })
+
+      const result = await api.listDayOverridesByWorkspace('ws1')
+
+      expect(result[0]!.note).toBeNull()
+      expect(result[0]!.createdAt).toBeNull()
+      expect(result[0]!.updatedAt).toBeNull()
+      expect(result[0]!.isWorkingDay).toBe(false)
+    })
+  })
 })
 
 describe('apiFetch (shared request/response handling)', () => {
@@ -1334,6 +1402,46 @@ describe('endpoint functions (representative coverage)', () => {
     ])
   })
 
+  it('applyPlan maps a populated collisions array to camelCase (§3.5)', async () => {
+    // The only other applyPlan mapping test passes collisions: [], so
+    // existing_day_type/proposed_day_type were never checked against real
+    // data — this exercises the actual field renames.
+    fetchMock.mockResolvedValue({
+      ok: true,
+      status: 200,
+      json: async () => ({
+        accepted: false,
+        created_count: 0,
+        skipped_identical_count: 0,
+        skipped_free_count: 0,
+        replaced_count: 0,
+        collisions: [
+          {
+            date: '2026-06-15',
+            parent_personal_data_uuid: 'pd1',
+            child_id: 'child1',
+            existing_day_type: 'vacation',
+            proposed_day_type: 'sjukpenning',
+          },
+        ],
+        rejections: [],
+        created_days: [],
+      }),
+    })
+
+    const result = await api.applyPlan('ws1', [], false)
+
+    expect(result.collisions).toEqual([
+      {
+        date: '2026-06-15',
+        parentPersonalDataUuid: 'pd1',
+        childId: 'child1',
+        existingDayType: 'vacation',
+        proposedDayType: 'sjukpenning',
+      },
+    ])
+  })
+
   it('syncPlan posts the workspace id and maps the nested proposal/applyResult/changes', async () => {
     fetchMock.mockResolvedValue({
       ok: true,