diff --git a/src/app/legacy/containers/ArticleTimestamp/index.stories.jsx b/src/app/legacy/containers/ArticleTimestamp/index.stories.jsx
index 17568ac090f..9995cbbf4fb 100644
--- a/src/app/legacy/containers/ArticleTimestamp/index.stories.jsx
+++ b/src/app/legacy/containers/ArticleTimestamp/index.stories.jsx
@@ -1,4 +1,5 @@
 import WithTimeMachine from '../../../../testHelpers/withTimeMachine';
+import { ServiceContextProvider } from '#app/contexts/ServiceContext';
 import ArticleTimestamp from '.';
 import { timestampGenerator } from './testHelpers';
 
@@ -93,3 +94,46 @@ export const H = () => (
 );
 H.storyName =
   'lastPublished today and more than 10 hours ago and firstPublished before today';
+
+// Timezone and locale migration checks for Moment → Temporal
+const timezoneLocaleServices = [
+  { service: 'news', label: 'English (Europe/London)' },
+  { service: 'azeri', label: 'Azeri (Asia/Baku)' },
+  { service: 'persian', label: 'Persian (GMT, Jalali calendar)' },
+  { service: 'arabic', label: 'Arabic (GMT, RTL)' },
+  { service: 'portuguese', label: 'Portuguese (America/Sao_Paulo)' },
+  { service: 'nepali', label: 'Nepali (Asia/Kathmandu)' },
+];
+
+const dstBoundaryTimestamp = Date.UTC(2021, 2, 28, 1, 0, 0); // 28 March 2021 01:00 UTC (DST boundary)
+const fixedOlderTimestamp = Date.UTC(2021, 2, 27, 12, 0, 0); // 27 March 2021 12:00 UTC
+
+export const TimezoneAndLocaleChecks = () => (
+  <div>
+    {timezoneLocaleServices.map(({ service, label }) => (
+      <ServiceContextProvider key={service} service={service}>
+        <div
+          style={{
+            marginBottom: '2rem',
+            padding: '1rem',
+            border: '1px solid #ccc',
+          }}
+        >
+          <strong>{label}</strong>
+          <div style={{ marginTop: '0.5rem' }}>
+            <ArticleTimestamp
+              firstPublished={fixedOlderTimestamp}
+              lastPublished={dstBoundaryTimestamp}
+            />
+          </div>
+        </div>
+      </ServiceContextProvider>
+    ))}
+  </div>
+);
+TimezoneAndLocaleChecks.parameters = {
+  chromatic: {
+    disable: false,
+  },
+};
+TimezoneAndLocaleChecks.tags = ['!dev'];
diff --git a/src/app/legacy/containers/ArticleTimestamp/timeFormatTests/README.md b/src/app/legacy/containers/ArticleTimestamp/timeFormatTests/README.md
index 5b5b23d8e8c..81f21d60b07 100644
--- a/src/app/legacy/containers/ArticleTimestamp/timeFormatTests/README.md
+++ b/src/app/legacy/containers/ArticleTimestamp/timeFormatTests/README.md
@@ -12,7 +12,7 @@ A couple of scenarios that we expect these tests would fail and need updating wo
 
 - Change in the timeformat logic [here](../timeFormats)
 
-- Changes in DST times across different timezones.
+- Changes in Daylight Saving Time (DST) times across different timezones.
 
 - ... please add more if you find any
 
diff --git a/src/app/legacy/containers/ArticleTimestamp/timeFormatTests/testUtils.js b/src/app/legacy/containers/ArticleTimestamp/timeFormatTests/testUtils.js
index 8d774147929..769ca1f96da 100644
--- a/src/app/legacy/containers/ArticleTimestamp/timeFormatTests/testUtils.js
+++ b/src/app/legacy/containers/ArticleTimestamp/timeFormatTests/testUtils.js
@@ -51,3 +51,23 @@ export const format = ({ datetimeLocale, timezone, fixture, altCalendar }) => {
 
   return formatted;
 };
+
+// allows precise checks for edge cases without fixture data
+export const formatTimestamp = ({
+  datetimeLocale,
+  timezone,
+  time,
+  altCalendar,
+  dateTimeFormat = formatDateAndTime,
+}) => {
+  const dateWithTimezone = moment.tz(time, timezone).locale(datetimeLocale);
+  const formatted = dateWithTimezone.format(dateTimeFormat(datetimeLocale));
+
+  if (altCalendar) {
+    const altCalendarFormatted = altCalendar.formatDate(dateWithTimezone);
+
+    return `${altCalendarFormatted} - ${formatted}`;
+  }
+
+  return formatted;
+};
diff --git a/src/app/legacy/containers/ArticleTimestamp/timeFormatTests/timeFormat.test.js b/src/app/legacy/containers/ArticleTimestamp/timeFormatTests/timeFormat.test.js
index 8d2d8e33d48..ae40af92ca1 100644
--- a/src/app/legacy/containers/ArticleTimestamp/timeFormatTests/timeFormat.test.js
+++ b/src/app/legacy/containers/ArticleTimestamp/timeFormatTests/timeFormat.test.js
@@ -1,6 +1,6 @@
 import services from '#utilities/serviceConfigs';
 import expectedFormats from './expectedFormats.json';
-import { format, timestampsFixtures } from './testUtils';
+import { format, formatTimestamp, timestampsFixtures } from './testUtils';
 
 describe('Timestamp Formats', () => {
   Object.keys(services).forEach(service => {
@@ -22,4 +22,81 @@ describe('Timestamp Formats', () => {
       });
     });
   });
+
+  describe('Timestamp Edge Cases', () => {
+    it('should preserve timezone output around DST start for Europe/London', () => {
+      const beforeDSTStart = Date.UTC(2021, 2, 28, 0, 30, 0); // 00:30 GMT
+      const afterDSTStart = Date.UTC(2021, 2, 28, 1, 30, 0); // 02:30 BST
+
+      expect(
+        formatTimestamp({
+          datetimeLocale: services.news.default.datetimeLocale,
+          timezone: services.news.default.timezone,
+          time: beforeDSTStart,
+        }),
+      ).toEqual('28 March 2021, 00:30 GMT');
+
+      expect(
+        formatTimestamp({
+          datetimeLocale: services.news.default.datetimeLocale,
+          timezone: services.news.default.timezone,
+          time: afterDSTStart,
+        }),
+      ).toEqual('28 March 2021, 02:30 BST');
+    });
+
+    it('should preserve timezone output around DST end for Europe/London', () => {
+      const beforeDSTEnd = Date.UTC(2021, 9, 31, 0, 30, 0); // 01:30 BST
+      const afterDSTEnd = Date.UTC(2021, 9, 31, 1, 30, 0); // 01:30 GMT
+
+      expect(
+        formatTimestamp({
+          datetimeLocale: services.news.default.datetimeLocale,
+          timezone: services.news.default.timezone,
+          time: beforeDSTEnd,
+        }),
+      ).toEqual('31 October 2021, 01:30 BST');
+
+      expect(
+        formatTimestamp({
+          datetimeLocale: services.news.default.datetimeLocale,
+          timezone: services.news.default.timezone,
+          time: afterDSTEnd,
+        }),
+      ).toEqual('31 October 2021, 01:30 GMT');
+    });
+
+    it('should preserve half-hour offset output for Asia/Kabul', () => {
+      const utcTimestamp = Date.UTC(2021, 5, 15, 12, 0, 0); // 15 June 2021 12:00 UTC
+
+      expect(
+        formatTimestamp({
+          datetimeLocale: services.dari.default.datetimeLocale,
+          timezone: services.dari.default.timezone,
+          time: utcTimestamp,
+        }),
+      ).toEqual('۱۵ جون ۲۰۲۱ ۱۶:۳۰');
+    });
+
+    it('should preserve timezone output around DST start for Europe/Bucharest', () => {
+      const beforeDSTStart = Date.UTC(2021, 2, 28, 0, 30, 0); // 02:30 EET
+      const afterDSTStart = Date.UTC(2021, 2, 28, 1, 30, 0); // 04:30 EEST
+
+      expect(
+        formatTimestamp({
+          datetimeLocale: services.romania.default.datetimeLocale,
+          timezone: services.romania.default.timezone,
+          time: beforeDSTStart,
+        }),
+      ).toEqual('28 martie 2021, 02:30 EET');
+
+      expect(
+        formatTimestamp({
+          datetimeLocale: services.romania.default.datetimeLocale,
+          timezone: services.romania.default.timezone,
+          time: afterDSTStart,
+        }),
+      ).toEqual('28 martie 2021, 04:30 EEST');
+    });
+  });
 });
diff --git a/src/app/legacy/psammead/psammead-timestamp-container/src/utilities/index.test.js b/src/app/legacy/psammead/psammead-timestamp-container/src/utilities/index.test.js
index b08ed082a76..92d84eda326 100644
--- a/src/app/legacy/psammead/psammead-timestamp-container/src/utilities/index.test.js
+++ b/src/app/legacy/psammead/psammead-timestamp-container/src/utilities/index.test.js
@@ -132,6 +132,143 @@ describe('Timestamp utility functions', () => {
       });
       expect(result).toBeUndefined();
     });
+
+    it('should correctly format timezone labels around DST start in Europe/London', () => {
+      const beforeDSTStart = Date.UTC(2021, 2, 28, 0, 30, 0); // 00:30 GMT
+      const afterDSTStart = Date.UTC(2021, 2, 28, 1, 30, 0); // 02:30 BST
+
+      expect(
+        formatUnixTimestamp({
+          timestamp: beforeDSTStart,
+          format: 'D MMMM YYYY, HH:mm z',
+          timezone,
+          locale,
+        }),
+      ).toEqual('28 March 2021, 00:30 GMT');
+
+      expect(
+        formatUnixTimestamp({
+          timestamp: afterDSTStart,
+          format: 'D MMMM YYYY, HH:mm z',
+          timezone,
+          locale,
+        }),
+      ).toEqual('28 March 2021, 02:30 BST');
+    });
+
+    it('should correctly format timezone labels around DST end in Europe/London', () => {
+      const beforeDSTEnd = Date.UTC(2021, 9, 31, 0, 30, 0); // 01:30 BST
+      const afterDSTEnd = Date.UTC(2021, 9, 31, 1, 30, 0); // 01:30 GMT
+
+      expect(
+        formatUnixTimestamp({
+          timestamp: beforeDSTEnd,
+          format: 'D MMMM YYYY, HH:mm z',
+          timezone,
+          locale,
+        }),
+      ).toEqual('31 October 2021, 01:30 BST');
+
+      expect(
+        formatUnixTimestamp({
+          timestamp: afterDSTEnd,
+          format: 'D MMMM YYYY, HH:mm z',
+          timezone,
+          locale,
+        }),
+      ).toEqual('31 October 2021, 01:30 GMT');
+    });
+
+    it('should apply a fixed UTC+1 offset for Africa/Lagos (no DST)', () => {
+      const utcTimestamp = Date.UTC(2021, 5, 15, 12, 0, 0); // 15 June 2021 12:00 UTC
+
+      expect(
+        formatUnixTimestamp({
+          timestamp: utcTimestamp,
+          format: 'D MMMM YYYY, HH:mm z',
+          timezone: 'Africa/Lagos',
+          locale,
+        }),
+      ).toEqual('15 June 2021, 13:00 WAT');
+    });
+
+    it('should apply a +05:45 offset for Asia/Kathmandu (no DST, non-whole-hour offset)', () => {
+      const utcTimestamp = Date.UTC(2021, 5, 15, 12, 0, 0); // 15 June 2021 12:00 UTC
+
+      expect(
+        formatUnixTimestamp({
+          timestamp: utcTimestamp,
+          format: 'D MMMM YYYY, HH:mm z',
+          timezone: 'Asia/Kathmandu',
+          locale,
+        }),
+      ).toEqual('15 June 2021, 17:45 +0545');
+    });
+
+    it('should apply a negative UTC-3 offset for America/Sao_Paulo', () => {
+      const utcTimestamp = Date.UTC(2021, 5, 15, 12, 0, 0); // 15 June 2021 12:00 UTC
+
+      expect(
+        formatUnixTimestamp({
+          timestamp: utcTimestamp,
+          format: 'D MMMM YYYY, HH:mm z',
+          timezone: 'America/Sao_Paulo',
+          locale,
+        }),
+      ).toEqual('15 June 2021, 09:00 -03');
+    });
+
+    it('should format correctly for GMT (non-region-style IANA identifier)', () => {
+      const utcTimestamp = Date.UTC(2021, 5, 15, 12, 0, 0); // 15 June 2021 12:00 UTC
+
+      expect(
+        formatUnixTimestamp({
+          timestamp: utcTimestamp,
+          format: 'D MMMM YYYY, HH:mm z',
+          timezone: 'GMT',
+          locale,
+        }),
+      ).toEqual('15 June 2021, 12:00 GMT');
+    });
+
+    it('should translate month names for a non-Latin locale', () => {
+      expect(
+        formatUnixTimestamp({
+          timestamp,
+          format: 'D MMMM YYYY',
+          timezone: 'GMT',
+          locale: 'ar',
+        }),
+      ).toEqual('١٩ أكتوبر ٢٠١٨');
+    });
+
+    it('should apply locale-sensitive format tokens (LL, LT) for a non-Latin locale', () => {
+      expect(
+        formatUnixTimestamp({
+          timestamp,
+          format: null,
+          timezone: 'GMT',
+          locale: 'ar',
+        }),
+      ).toEqual('١٩ أكتوبر ٢٠١٨، ١٧:١٠ GMT');
+    });
+
+    it('should return relative timestamp in the provided locale', () => {
+      const nowSpy = jest.spyOn(Date, 'now').mockReturnValue(1704110400000); // 1 January 2024 12:00:00 UTC
+      try {
+        const nineHoursAgo = timestampGenerator({ hours: 9 });
+        const output = formatUnixTimestamp({
+          timestamp: nineHoursAgo,
+          format: 'D MMMM YYYY',
+          timezone: 'GMT',
+          locale: 'ar',
+          isRelative: true,
+        });
+        expect(output).toEqual('منذ ٩ ساعات');
+      } finally {
+        nowSpy.mockRestore();
+      }
+    });
   });
 });
 
diff --git a/src/app/lib/config/services/azeri.ts b/src/app/lib/config/services/azeri.ts
index 72d91879179..0a2790f51dd 100644
--- a/src/app/lib/config/services/azeri.ts
+++ b/src/app/lib/config/services/azeri.ts
@@ -464,7 +464,7 @@ export const service: DefaultServiceConfig = {
       ],
       copyrightText: 'BBC. BBC kənar saytların məzmununa məsul deyil.',
     },
-    timezone: 'Asia/baku',
+    timezone: 'Asia/Baku',
     navigation: [
       {
         title: 'Xəbərlər',