diff --git a/api-v3/src/database/migrations/1790099200000-reset-operational-hierarchy-data.ts b/api-v3/src/database/migrations/1790099200000-reset-operational-hierarchy-data.ts
index c09ecd1..4c2cb70 100644
--- a/api-v3/src/database/migrations/1790099200000-reset-operational-hierarchy-data.ts
+++ b/api-v3/src/database/migrations/1790099200000-reset-operational-hierarchy-data.ts
@@ -32,6 +32,27 @@ export class ResetOperationalHierarchyData1790099200000 implements MigrationInte
   name = 'ResetOperationalHierarchyData1790099200000';
 
   public async up(queryRunner: QueryRunner): Promise<void> {
+    // This is a one-time live-data cleanup, not a new canonical empty seed.
+    // Fresh CI/bootstrap databases intentionally have no admin account while
+    // replaying the historical migration chain, so they must retain the F6.1
+    // presentation seed used by hierarchy/planning contract tests.
+    const adminRows = (await queryRunner.query(`
+      SELECT id
+      FROM users
+      WHERE lower(btrim(username))='admin'
+      ORDER BY id
+    `)) as Array<{ id: string }>;
+    if (adminRows.length === 0) {
+      // eslint-disable-next-line no-console
+      console.log('[hierarchy-reset] skipped: no live admin account on migration replay');
+      return;
+    }
+    if (adminRows.length !== 1) {
+      throw new Error(
+        `Hierarchy reset aborted: expected exactly one live admin account, found ${adminRows.length}`,
+      );
+    }
+
     const targetTypes = (await queryRunner.query(
       `
       SELECT lower(code) AS code