diff --git a/packages/shared-components/src/event-tiles/DateSeparator/DateSeparator.module.css b/packages/shared-components/src/event-tiles/DateSeparator/DateSeparator.module.css
index 02df06a514..108950a057 100644
--- a/packages/shared-components/src/event-tiles/DateSeparator/DateSeparator.module.css
+++ b/packages/shared-components/src/event-tiles/DateSeparator/DateSeparator.module.css
@@ -1,5 +1,5 @@
 /*
- * Copyright 2025 New Vector Ltd.
+ * Copyright 2025 Element Creations Ltd.
  * Copyright 2017 Vector Creations Ltd
  *
  * SPDX-License-Identifier: AGPL-3.0-only OR GPL-3.0-only OR LicenseRef-Element-Commercial
diff --git a/packages/shared-components/src/event-tiles/DateSeparator/DateSeparator.stories.tsx b/packages/shared-components/src/event-tiles/DateSeparator/DateSeparator.stories.tsx
index 9c5785250b..99e543cbba 100644
--- a/packages/shared-components/src/event-tiles/DateSeparator/DateSeparator.stories.tsx
+++ b/packages/shared-components/src/event-tiles/DateSeparator/DateSeparator.stories.tsx
@@ -1,5 +1,5 @@
 /*
- * Copyright 2025 New Vector Ltd.
+ * Copyright 2025 Element Creations Ltd.
  *
  * SPDX-License-Identifier: AGPL-3.0-only OR GPL-3.0-only OR LicenseRef-Element-Commercial
  * Please see LICENSE files in the repository root for full details.
diff --git a/packages/shared-components/src/event-tiles/DateSeparator/DateSeparator.test.tsx b/packages/shared-components/src/event-tiles/DateSeparator/DateSeparator.test.tsx
index bc86317fa5..cd9e4cdd6e 100644
--- a/packages/shared-components/src/event-tiles/DateSeparator/DateSeparator.test.tsx
+++ b/packages/shared-components/src/event-tiles/DateSeparator/DateSeparator.test.tsx
@@ -1,5 +1,5 @@
 /*
- * Copyright 2025 New Vector Ltd.
+ * Copyright 2025 Element Creations Ltd.
  *
  * SPDX-License-Identifier: AGPL-3.0-only OR GPL-3.0-only OR LicenseRef-Element-Commercial
  * Please see LICENSE files in the repository root for full details.
diff --git a/packages/shared-components/src/event-tiles/DateSeparator/DateSeparator.tsx b/packages/shared-components/src/event-tiles/DateSeparator/DateSeparator.tsx
index ec445427ce..f67414f396 100644
--- a/packages/shared-components/src/event-tiles/DateSeparator/DateSeparator.tsx
+++ b/packages/shared-components/src/event-tiles/DateSeparator/DateSeparator.tsx
@@ -1,5 +1,5 @@
 /*
- * Copyright 2025 New Vector Ltd.
+ * Copyright 2025 Element Creations Ltd.
  * Copyright 2015-2021 The Matrix.org Foundation C.I.C.
  * Copyright 2018 Michael Telatynski <7t3chguy@gmail.com>
  *
diff --git a/packages/shared-components/src/event-tiles/DateSeparator/index.tsx b/packages/shared-components/src/event-tiles/DateSeparator/index.tsx
index 05a24d317d..94bba09c48 100644
--- a/packages/shared-components/src/event-tiles/DateSeparator/index.tsx
+++ b/packages/shared-components/src/event-tiles/DateSeparator/index.tsx
@@ -1,5 +1,5 @@
 /*
- * Copyright 2025 New Vector Ltd.
+ * Copyright 2025 Element Creations Ltd.
  *
  * SPDX-License-Identifier: AGPL-3.0-only OR GPL-3.0-only OR LicenseRef-Element-Commercial
  * Please see LICENSE files in the repository root for full details.
diff --git a/packages/shared-components/src/utils/DateUtils.test.ts b/packages/shared-components/src/utils/DateUtils.test.ts
new file mode 100644
index 0000000000..50d7f80b2b
--- /dev/null
+++ b/packages/shared-components/src/utils/DateUtils.test.ts
@@ -0,0 +1,126 @@
+/*
+ * Copyright 2025 Element Creations Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR GPL-3.0-only OR LicenseRef-Element-Commercial
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+import { DAY_MS, getDaysArray, formatFullDateNoTime, formatSeconds } from "./DateUtils";
+
+describe("DateUtils", () => {
+    describe("DAY_MS", () => {
+        it("should equal the number of milliseconds in a day", () => {
+            expect(DAY_MS).toBe(24 * 60 * 60 * 1000);
+            expect(DAY_MS).toBe(86400000);
+        });
+    });
+
+    describe("getDaysArray", () => {
+        it("should return 7 days starting with Sunday", () => {
+            const days = getDaysArray("short", "en");
+            expect(days).toHaveLength(7);
+            expect(days[0]).toBe("Sun");
+            expect(days[1]).toBe("Mon");
+            expect(days[6]).toBe("Sat");
+        });
+
+        it("should use short format by default", () => {
+            const days = getDaysArray(undefined, "en");
+            expect(days).toHaveLength(7);
+            expect(days[0]).toBe("Sun");
+        });
+
+        it("should use en locale by default", () => {
+            const days = getDaysArray("short");
+            expect(days).toHaveLength(7);
+            expect(days[0]).toBe("Sun");
+        });
+
+        it("should support long weekday format", () => {
+            const days = getDaysArray("long", "en");
+            expect(days).toHaveLength(7);
+            expect(days[0]).toBe("Sunday");
+            expect(days[1]).toBe("Monday");
+            expect(days[6]).toBe("Saturday");
+        });
+
+        it("should support narrow weekday format", () => {
+            const days = getDaysArray("narrow", "en");
+            expect(days).toHaveLength(7);
+            expect(days[0]).toBe("S");
+            expect(days[1]).toBe("M");
+        });
+
+        it("should support different locales", () => {
+            const daysFr = getDaysArray("long", "fr");
+            expect(daysFr).toHaveLength(7);
+            expect(daysFr[0]).toBe("dimanche");
+            expect(daysFr[1]).toBe("lundi");
+        });
+    });
+
+    describe("formatFullDateNoTime", () => {
+        it("should format date with short weekday, month, day and year", () => {
+            const date = new Date("2022-11-17T12:00:00Z");
+            const formatted = formatFullDateNoTime(date, "en-GB");
+            expect(formatted).toContain("Nov");
+            expect(formatted).toContain("17");
+            expect(formatted).toContain("2022");
+        });
+
+        it("should use en locale by default", () => {
+            const date = new Date("2022-11-17T12:00:00Z");
+            const formatted = formatFullDateNoTime(date);
+            expect(formatted).toContain("Nov");
+            expect(formatted).toContain("17");
+            expect(formatted).toContain("2022");
+        });
+
+        it("should format dates in different locales", () => {
+            const date = new Date("2022-11-17T12:00:00Z");
+            const formattedFr = formatFullDateNoTime(date, "fr");
+            expect(formattedFr).toContain("nov.");
+            expect(formattedFr).toContain("17");
+            expect(formattedFr).toContain("2022");
+        });
+    });
+
+    describe("formatSeconds", () => {
+        it("should format seconds only", () => {
+            expect(formatSeconds(45)).toBe("00:45");
+        });
+
+        it("should format minutes and seconds", () => {
+            expect(formatSeconds(125)).toBe("02:05");
+        });
+
+        it("should format hours, minutes and seconds", () => {
+            expect(formatSeconds(3665)).toBe("01:01:05");
+        });
+
+        it("should pad with zeros", () => {
+            expect(formatSeconds(5)).toBe("00:05");
+            expect(formatSeconds(65)).toBe("01:05");
+        });
+
+        it("should handle zero", () => {
+            expect(formatSeconds(0)).toBe("00:00");
+        });
+
+        it("should handle negative numbers", () => {
+            expect(formatSeconds(-45)).toBe("-00:45");
+            expect(formatSeconds(-125)).toBe("-02:05");
+            expect(formatSeconds(-3665)).toBe("-01:01:05");
+        });
+
+        it("should handle large durations", () => {
+            expect(formatSeconds(36000)).toBe("10:00:00");
+            expect(formatSeconds(359999)).toBe("99:59:59");
+        });
+
+        it("should handle fractional seconds by flooring", () => {
+            expect(formatSeconds(45.9)).toBe("00:45");
+            expect(formatSeconds(125.5)).toBe("02:05");
+        });
+    });
+});