From 4306a7b5e3165f2b5922ffb4f1210494068a34e0 Mon Sep 17 00:00:00 2001
From: Anna Beddow <anna.beddow@gmail.com>
Date: Mon, 24 Aug 2026 17:14:33 +0100
Subject: [PATCH 1/2] Limit editorial headline AB testing to the US network
 front during initial testing.

---
 dotcom-rendering/src/model/enhanceCards.ts | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/dotcom-rendering/src/model/enhanceCards.ts b/dotcom-rendering/src/model/enhanceCards.ts
index 3ce42617218..f58f4e23382 100644
--- a/dotcom-rendering/src/model/enhanceCards.ts
+++ b/dotcom-rendering/src/model/enhanceCards.ts
@@ -237,6 +237,12 @@ export const decideHeadline = (
 
 	if (!testCanRunOnPage) return defaultHeadline;
 
+	/*
+	 * Initial rollout of Editorial AB testing will be limited to the US front only.
+	 * Removal of this front restriction will be covered by https://github.com/guardian/frontend/issues/29129
+	 */
+	if (pageId !== 'us') return defaultHeadline;
+
 	const variantMeta = activeEditorialTest.variantMeta.find(
 		(variant) => variant.id.toLowerCase() === testBucket,
 	);

From df0d1e670fd6c171d583663e49b1fb116be68fc8 Mon Sep 17 00:00:00 2001
From: Anna Beddow <anna.beddow@gmail.com>
Date: Mon, 24 Aug 2026 17:14:45 +0100
Subject: [PATCH 2/2] Update tests to use the US front as the front ID

---
 .../src/model/enhanceCards.test.ts            | 22 +++++++++----------
 1 file changed, 11 insertions(+), 11 deletions(-)

diff --git a/dotcom-rendering/src/model/enhanceCards.test.ts b/dotcom-rendering/src/model/enhanceCards.test.ts
index 6cd200a41c3..ff403487b3a 100644
--- a/dotcom-rendering/src/model/enhanceCards.test.ts
+++ b/dotcom-rendering/src/model/enhanceCards.test.ts
@@ -603,7 +603,7 @@ describe('Enhance Cards', () => {
 						] as VariantMeta[],
 						startDate: Date.now() - oneHourInMilliseconds,
 						expiryDate: Date.now() + oneHourInMilliseconds,
-						frontsThisTestCanRunOn: ['test-front'],
+						frontsThisTestCanRunOn: ['us'],
 						hasManuallyEndedOnThisTrail: false,
 					},
 				],
@@ -669,7 +669,7 @@ describe('Enhance Cards', () => {
 
 		it('returns the default headline if editorial test exists and page is in allowed fronts list, but user is not in a test bucket', () => {
 			expect(
-				decideHeadline(cardWithEditorialTest, {}, true, 'test-front'),
+				decideHeadline(cardWithEditorialTest, {}, true, 'us'),
 			).toEqual('Headline');
 		});
 
@@ -681,7 +681,7 @@ describe('Enhance Cards', () => {
 						'fronts-and-curation-editorial-headline-test': 'a',
 					},
 					true,
-					'test-front',
+					'us',
 				),
 			).toEqual('Headline');
 		});
@@ -694,7 +694,7 @@ describe('Enhance Cards', () => {
 						'fronts-and-curation-editorial-headline-test': 'a',
 					},
 					true,
-					'invalid-test-front',
+					'invalid-us',
 				),
 			).toEqual('Headline');
 		});
@@ -707,7 +707,7 @@ describe('Enhance Cards', () => {
 						'fronts-and-curation-editorial-headline-test': 'a',
 					},
 					false,
-					'test-front',
+					'us',
 				),
 			).toEqual('Headline');
 		});
@@ -720,7 +720,7 @@ describe('Enhance Cards', () => {
 						'fronts-and-curation-editorial-headline-test': 'a',
 					},
 					true,
-					'test-front',
+					'us',
 				),
 			).toEqual('Headline A');
 		});
@@ -733,7 +733,7 @@ describe('Enhance Cards', () => {
 						'fronts-and-curation-editorial-headline-test': 'b',
 					},
 					true,
-					'test-front',
+					'us',
 				),
 			).toEqual('Headline B');
 		});
@@ -746,7 +746,7 @@ describe('Enhance Cards', () => {
 						'fronts-and-curation-editorial-headline-test': 'c',
 					},
 					true,
-					'test-front',
+					'us',
 				),
 			).toEqual('Headline');
 		});
@@ -759,7 +759,7 @@ describe('Enhance Cards', () => {
 						'fronts-and-curation-editorial-headline-test': 'a',
 					},
 					true,
-					'test-front',
+					'us',
 				),
 			).toEqual('Headline');
 		});
@@ -772,7 +772,7 @@ describe('Enhance Cards', () => {
 						'fronts-and-curation-editorial-headline-test': 'a',
 					},
 					true,
-					'test-front',
+					'us',
 				),
 			).toEqual('Headline');
 		});
@@ -785,7 +785,7 @@ describe('Enhance Cards', () => {
 						'fronts-and-curation-editorial-headline-test': 'a',
 					},
 					true,
-					'test-front',
+					'us',
 				),
 			).toEqual('Headline');
 		});