diff --git a/src/server/services/__tests__/build.test.ts b/src/server/services/__tests__/build.test.ts
index 6d42691..4123b89 100644
--- a/src/server/services/__tests__/build.test.ts
+++ b/src/server/services/__tests__/build.test.ts
@@ -660,6 +660,54 @@ describe('BuildService destroyBuildEnvironment', () => {
   });
 });
 
+describe('BuildService getEnvironmentsToBuild', () => {
+  const createService = (foundEnvironment: any) =>
+    new BuildService(
+      {
+        models: {
+          Environment: {
+            findOne: jest.fn().mockResolvedValue(foundEnvironment),
+            // Phase 1 removed Environment.relationMappings.services. The old else-branch called
+            // Environment.find().withGraphJoined('services'), which throws UnknownRelationError.
+            find: jest.fn(() => {
+              throw new Error('Environment.find() must not be called: the DB-service lookup was removed');
+            }),
+          },
+        },
+      } as any,
+      {} as any,
+      {} as any,
+      {
+        registerQueue: jest.fn(() => ({ add: jest.fn(), process: jest.fn(), on: jest.fn() })),
+      } as any
+    );
+
+  beforeEach(() => {
+    jest.clearAllMocks();
+  });
+
+  test('returns the environment for a known environmentId', async () => {
+    const environment = { id: 7 };
+    const service = createService(environment);
+
+    await expect((service as any).getEnvironmentsToBuild(7)).resolves.toEqual([environment]);
+  });
+
+  test('returns empty for a null environmentId instead of querying the removed services relation', async () => {
+    const service = createService(undefined);
+
+    await expect((service as any).getEnvironmentsToBuild(null)).resolves.toEqual([]);
+    expect((service as any).db.models.Environment.find).not.toHaveBeenCalled();
+  });
+
+  test('returns empty when the environment is missing rather than a list holding undefined', async () => {
+    const service = createService(undefined);
+
+    // toStrictEqual: toEqual treats [undefined] as [], which would hide the old push-undefined behaviour.
+    await expect((service as any).getEnvironmentsToBuild(99)).resolves.toStrictEqual([]);
+  });
+});
+
 describe('BuildService stale deploy reconciliation', () => {
   let buildService: BuildService;
   let deployableQuery: any;
diff --git a/src/server/services/build.ts b/src/server/services/build.ts
index 249628e..3ff11f8 100644
--- a/src/server/services/build.ts
+++ b/src/server/services/build.ts
@@ -2079,7 +2079,7 @@ export default class BuildService extends BaseService {
     environmentId,
     lifecycleConfig,
   }: DeployOptions & { repositoryId: number }) {
-    const environments = await this.getEnvironmentsToBuild(environmentId, repositoryId);
+    const environments = await this.getEnvironmentsToBuild(environmentId);
 
     if (!environments.length) {
       getLogger().debug('Build: no matching environments');
@@ -3214,19 +3214,15 @@ export default class BuildService extends BaseService {
   /**
    * Returns an array of environments to build.
    * @param environmentId the default environmentId (if one exists)
-   * @param repositoryId the repository to use for finding relevant environments, if needed
    */
-  private async getEnvironmentsToBuild(environmentId: number, repositoryId: number) {
-    let environments: Environment[] = [];
-    if (environmentId != null) {
-      environments.push(await this.db.models.Environment.findOne({ id: environmentId }));
-    } else {
-      environments = environments.concat(
-        await this.db.models.Environment.find().withGraphJoined('services').where('services.repositoryId', repositoryId)
-      );
+  private async getEnvironmentsToBuild(environmentId: number): Promise<Environment[]> {
+    if (environmentId == null) {
+      return [];
     }
 
-    return environments;
+    const environment = await this.db.models.Environment.findOne({ id: environmentId });
+
+    return environment != null ? [environment] : [];
   }
 
   private async updateDeploysImageDetails(build: Build, githubRepositoryId?: number, sourceBranch?: string | null) {