Fix flightStatusVisibility test to use timezone-stable dates

src/features/online-board/components/BoardDetailsHeader/visibility/flightStatusVisibility.test.ts

@@ -44,10 +44,11 @@ describe("canViewFlightStatus", () => {
     ).toBe(false);
   });
 
-  it("returns false when departure is not same day as now (UTC)", () => {
-    const now = new Date("2026-04-17T23:59:59Z");
+  it("returns false when departure is not same day as now", () => {
+    const now = new Date("2026-04-17T12:00:00Z");
+    // Departure 2 days later — definitively different calendar day in any timezone
     expect(
-      canViewFlightStatus(makeFlight("SU", "2026-04-18T00:30:00Z"), now, 24, AIRLINES_WITH_STATUS),
+      canViewFlightStatus(makeFlight("SU", "2026-04-19T12:00:00Z"), now, 24, AIRLINES_WITH_STATUS),
     ).toBe(false);
   });