diff --git a/backend/.sqlx/query-08a3f282c1f8bded7991baeb5dc14131e707e4438fd1ddf38112fe66ad625691.json b/backend/.sqlx/query-08a3f282c1f8bded7991baeb5dc14131e707e4438fd1ddf38112fe66ad625691.json
new file mode 100644
index 0000000000..607ccbc62a
--- /dev/null
+++ b/backend/.sqlx/query-08a3f282c1f8bded7991baeb5dc14131e707e4438fd1ddf38112fe66ad625691.json
@@ -0,0 +1,16 @@
+{
+  "db_name": "PostgreSQL",
+  "query": "UPDATE app SET policy = jsonb_set(policy, ARRAY['on_behalf_of'], to_jsonb($1::text))\n         WHERE policy->>'on_behalf_of' = $2 AND workspace_id = $3",
+  "describe": {
+    "columns": [],
+    "parameters": {
+      "Left": [
+        "Text",
+        "Text",
+        "Text"
+      ]
+    },
+    "nullable": []
+  },
+  "hash": "08a3f282c1f8bded7991baeb5dc14131e707e4438fd1ddf38112fe66ad625691"
+}
diff --git a/backend/.sqlx/query-7dc111544e885bb1d549b9da2a03c8ad60b62797f52cb5d8f153e19b001a33ec.json b/backend/.sqlx/query-7dc111544e885bb1d549b9da2a03c8ad60b62797f52cb5d8f153e19b001a33ec.json
new file mode 100644
index 0000000000..8d660cfc94
--- /dev/null
+++ b/backend/.sqlx/query-7dc111544e885bb1d549b9da2a03c8ad60b62797f52cb5d8f153e19b001a33ec.json
@@ -0,0 +1,16 @@
+{
+  "db_name": "PostgreSQL",
+  "query": "UPDATE draft SET value = to_json(jsonb_set(to_jsonb(value), ARRAY['policy', 'on_behalf_of'], to_jsonb($1::text)))\n               WHERE typ IN ('app', 'raw_app')\n                 AND value->'policy'->>'on_behalf_of' = $2\n                 AND NOT EXISTS (\n                   SELECT 1 FROM usr WHERE usr.workspace_id = draft.workspace_id AND usr.username = $3\n                 )",
+  "describe": {
+    "columns": [],
+    "parameters": {
+      "Left": [
+        "Text",
+        "Text",
+        "Text"
+      ]
+    },
+    "nullable": []
+  },
+  "hash": "7dc111544e885bb1d549b9da2a03c8ad60b62797f52cb5d8f153e19b001a33ec"
+}
diff --git a/backend/.sqlx/query-c38271cd19861d39f7070799c8ee5eec2d171431d3ce710263eeb16010becfae.json b/backend/.sqlx/query-c38271cd19861d39f7070799c8ee5eec2d171431d3ce710263eeb16010becfae.json
new file mode 100644
index 0000000000..1dab1e5b71
--- /dev/null
+++ b/backend/.sqlx/query-c38271cd19861d39f7070799c8ee5eec2d171431d3ce710263eeb16010becfae.json
@@ -0,0 +1,16 @@
+{
+  "db_name": "PostgreSQL",
+  "query": "UPDATE draft SET value = to_json(jsonb_set(to_jsonb(value), ARRAY['policy', 'on_behalf_of'], to_jsonb($1::text))) WHERE typ IN ('app', 'raw_app') AND value->'policy'->>'on_behalf_of' = $2 AND workspace_id = $3",
+  "describe": {
+    "columns": [],
+    "parameters": {
+      "Left": [
+        "Text",
+        "Text",
+        "Text"
+      ]
+    },
+    "nullable": []
+  },
+  "hash": "c38271cd19861d39f7070799c8ee5eec2d171431d3ce710263eeb16010becfae"
+}
diff --git a/backend/.sqlx/query-ce4976f6708001a667b0fe6189e46fdb95f9f1cd41ebe42551149ad26578d4ef.json b/backend/.sqlx/query-ce4976f6708001a667b0fe6189e46fdb95f9f1cd41ebe42551149ad26578d4ef.json
new file mode 100644
index 0000000000..0ea9260ce1
--- /dev/null
+++ b/backend/.sqlx/query-ce4976f6708001a667b0fe6189e46fdb95f9f1cd41ebe42551149ad26578d4ef.json
@@ -0,0 +1,16 @@
+{
+  "db_name": "PostgreSQL",
+  "query": "UPDATE app SET policy = jsonb_set(policy, ARRAY['on_behalf_of'], to_jsonb($1::text))\n             WHERE policy->>'on_behalf_of' = $2\n               AND NOT EXISTS (\n                 SELECT 1 FROM usr WHERE usr.workspace_id = app.workspace_id AND usr.username = $3\n               )",
+  "describe": {
+    "columns": [],
+    "parameters": {
+      "Left": [
+        "Text",
+        "Text",
+        "Text"
+      ]
+    },
+    "nullable": []
+  },
+  "hash": "ce4976f6708001a667b0fe6189e46fdb95f9f1cd41ebe42551149ad26578d4ef"
+}
diff --git a/backend/windmill-api-integration-tests/tests/fork_clone_on_behalf_of.rs b/backend/windmill-api-integration-tests/tests/fork_clone_on_behalf_of.rs
index dae02f3e5a..7778069b9b 100644
--- a/backend/windmill-api-integration-tests/tests/fork_clone_on_behalf_of.rs
+++ b/backend/windmill-api-integration-tests/tests/fork_clone_on_behalf_of.rs
@@ -20,7 +20,6 @@ async fn fork_with_public_app(
          RETURNING id",
         json!({
             "on_behalf_of": "u/test-user",
-            "on_behalf_of_email": "test@windmill.dev",
             "execution_mode": "anonymous",
         })
     )
@@ -71,7 +70,6 @@ async fn test_fork_repoints_app_identity_for_unprivileged_creator(
     let (policy, custom_path) = fork_with_public_app(&db, "SECRET_TOKEN_2").await?;
 
     assert_eq!(policy["on_behalf_of"], json!("u/test-user-2"));
-    assert_eq!(policy["on_behalf_of_email"], json!("test2@windmill.dev"));
     // `execution_mode` rides along untouched — see `clone_apps`.
     assert_eq!(policy["execution_mode"], json!("anonymous"));
     assert_eq!(custom_path, None);
@@ -88,7 +86,6 @@ async fn test_fork_keeps_app_policy_for_admin_creator(db: Pool<Postgres>) -> any
     let (policy, custom_path) = fork_with_public_app(&db, "SECRET_TOKEN").await?;
 
     assert_eq!(policy["on_behalf_of"], json!("u/test-user"));
-    assert_eq!(policy["on_behalf_of_email"], json!("test@windmill.dev"));
     assert_eq!(policy["execution_mode"], json!("anonymous"));
     assert_eq!(custom_path, None);
 
@@ -113,7 +110,7 @@ async fn test_compare_ignores_app_identity(db: Pool<Postgres>) -> anyhow::Result
              VALUES ('test-workspace', $1, 'original', $2, '{}')
              RETURNING id",
             path,
-            json!({ "on_behalf_of": "u/test-user", "on_behalf_of_email": "test@windmill.dev" })
+            json!({ "on_behalf_of": "u/test-user" })
         )
         .fetch_one(&db)
         .await?;
@@ -147,7 +144,7 @@ async fn test_compare_ignores_app_identity(db: Pool<Postgres>) -> anyhow::Result
     sqlx::query!(
         "UPDATE app SET policy = policy || $1::jsonb
          WHERE workspace_id = 'wm-fork-cmp' AND path = 'u/test-user/identity_only'",
-        json!({ "on_behalf_of": "u/someone-else", "on_behalf_of_email": "else@windmill.dev" })
+        json!({ "on_behalf_of": "u/someone-else" })
     )
     .execute(&db)
     .await?;
diff --git a/backend/windmill-api-integration-tests/tests/users.rs b/backend/windmill-api-integration-tests/tests/users.rs
index 65d44509d7..56ca64c832 100644
--- a/backend/windmill-api-integration-tests/tests/users.rs
+++ b/backend/windmill-api-integration-tests/tests/users.rs
@@ -622,7 +622,7 @@ async fn test_change_user_email(db: Pool<Postgres>) -> anyhow::Result<()> {
     .await?;
     sqlx::query!(
         "INSERT INTO app(workspace_id, path, summary, policy, versions)
-         VALUES ('test-workspace', 'u/test-user-2/app', '', '{\"on_behalf_of\": \"test2@windmill.dev\", \"on_behalf_of_email\": \"test2@windmill.dev\"}'::jsonb, '{}')"
+         VALUES ('test-workspace', 'u/test-user-2/app', '', '{\"on_behalf_of\": \"test2@windmill.dev\"}'::jsonb, '{}')"
     )
     .execute(&db)
     .await?;
@@ -827,14 +827,6 @@ async fn test_change_user_email_leaves_group_identities(db: Pool<Postgres>) -> a
     // moves is the address beside it — kept for the workers that still read it — and in every
     // pair a group-owned identity keeps the group's synthetic address even though a real account
     // now holds it: rewriting one half leaves the pair naming two accounts.
-    sqlx::query!(
-        "INSERT INTO app(workspace_id, path, summary, policy, versions)
-         VALUES ('test-workspace', 'u/test-user/g', '', '{\"on_behalf_of\": \"g/ops\", \"on_behalf_of_email\": \"group-ops@windmill.dev\"}'::jsonb, '{}'),
-                ('test-workspace', 'u/test-user/u', '', '{\"on_behalf_of\": \"u/test-user-2\", \"on_behalf_of_email\": \"group-ops@windmill.dev\"}'::jsonb, '{}')"
-    )
-    .execute(&db)
-    .await?;
-
     sqlx::query!(
         "INSERT INTO script (workspace_id, path, hash, content, summary, description, language, created_by, created_at, on_behalf_of, on_behalf_of_email)
          VALUES ('test-workspace', 'u/test-user/sg', 95001, 'def main(): pass', '', '', 'python3', 'test-user', NOW(), 'g/ops', 'group-ops@windmill.dev'),
@@ -857,22 +849,6 @@ async fn test_change_user_email_leaves_group_identities(db: Pool<Postgres>) -> a
         .await?;
     assert_eq!(resp.status(), 200, "change_email: {}", resp.text().await?);
 
-    let apps = sqlx::query!(
-        "SELECT path, policy->>'on_behalf_of_email' AS email FROM app WHERE workspace_id = 'test-workspace' ORDER BY path"
-    )
-    .fetch_all(&db)
-    .await?;
-    assert_eq!(
-        apps.iter()
-            .map(|r| (r.path.as_str(), r.email.as_deref()))
-            .collect::<Vec<_>>(),
-        vec![
-            ("u/test-user/g", Some("group-ops@windmill.dev")),
-            ("u/test-user/u", Some("renamed@windmill.dev")),
-        ],
-        "the group-owned app keeps the group's address; the user-owned one moves"
-    );
-
     let scripts = sqlx::query!(
         "SELECT path, on_behalf_of_email AS email FROM script WHERE workspace_id = 'test-workspace' AND path LIKE 'u/test-user/s%' ORDER BY path"
     )
diff --git a/backend/windmill-api-users/src/users.rs b/backend/windmill-api-users/src/users.rs
index 260df2f969..8b6371f5b5 100644
--- a/backend/windmill-api-users/src/users.rs
+++ b/backend/windmill-api-users/src/users.rs
@@ -2062,19 +2062,6 @@ async fn change_user_email(
     .execute(&mut *tx)
     .await?;
 
-    // Apps store an address next to their principal, and the synthetic
-    // `group-{name}@windmill.dev` may be a real user's, so a group-owned app has to keep its
-    // address when a colliding user moves: an app running in Anonymous or Publisher mode takes
-    // its permissions from that pair rather than from the caller, and a half-rewritten pair
-    // names two accounts. Drafts below carry the same pair and need the same guard.
-    sqlx::query!(
-        "UPDATE app SET policy = jsonb_set(policy, ARRAY['on_behalf_of_email'], to_jsonb($1::text)) WHERE policy->>'on_behalf_of_email' = $2 AND (policy->>'on_behalf_of' IS NULL OR policy->>'on_behalf_of' NOT LIKE 'g/%')",
-        &new_email,
-        &old_email
-    )
-    .execute(&mut *tx)
-    .await?;
-
     // ---- permissioned_as naming the account by its address ----
     // `usr.username` is constrained to `[\w-]+`, so a workspace member is always named
     // `u/{username}` and their principals survive an address change untouched. The address form
@@ -2103,8 +2090,9 @@ async fn change_user_email(
 
     // The address these two keep beside the principal is what a worker predating
     // MIN_VERSION_SUPPORTS_ON_BEHALF_OF_PRINCIPAL reads, so it follows the account for as long
-    // as one may be live. Group-owned rows are held back for the reason given above the app
-    // sweep: their address is the group's, which a colliding user does not take with them.
+    // as one may be live. Group-owned rows are held back: the synthetic
+    // `group-{name}@windmill.dev` may be a real user's, and their address is the group's, which
+    // a colliding user does not take with them — a half-rewritten pair names two accounts.
     sqlx::query!(
         "UPDATE script SET on_behalf_of_email = $1 WHERE on_behalf_of_email = $2 AND (on_behalf_of IS NULL OR on_behalf_of NOT LIKE 'g/%')",
         &new_email,
@@ -2132,7 +2120,7 @@ async fn change_user_email(
     // Script/flow rows store only the principal, but drafts carry an address beside it and
     // `deployDraft` sends both — left stale it contradicts the principal, which resolves to the
     // new address, and the deploy is rejected. Group-owned drafts are held back for the reason
-    // given above the app sweep.
+    // given above the script sweep.
     sqlx::query!(
         r#"UPDATE draft SET value = to_json(jsonb_set(to_jsonb(value), ARRAY['on_behalf_of_email'], to_jsonb($1::text))) WHERE typ IN ('script', 'flow') AND value->>'on_behalf_of_email' = $2 AND (value->>'on_behalf_of' IS NULL OR value->>'on_behalf_of' NOT LIKE 'g/%')"#,
         &new_email,
@@ -2158,19 +2146,6 @@ async fn change_user_email(
     .execute(&mut *tx)
     .await?;
 
-    // A raw-app draft persists the address the client read back too. The deploy sends it beside
-    // the principal, where an address naming somebody else is rejected — and unlike a live read
-    // it never refreshes on its own. Same group guard as the deployed policy above, plus the
-    // `IS NULL` arm: without it the predicate is `NULL` for a draft with no principal, which is
-    // neither true nor false, so those rows would be skipped.
-    sqlx::query!(
-        r#"UPDATE draft SET value = to_json(jsonb_set(to_jsonb(value), ARRAY['policy', 'on_behalf_of_email'], to_jsonb($1::text))) WHERE typ IN ('app', 'raw_app') AND value->'policy'->>'on_behalf_of_email' = $2 AND (value->'policy'->>'on_behalf_of' IS NULL OR value->'policy'->>'on_behalf_of' NOT LIKE 'g/%')"#,
-        &new_email,
-        &old_email
-    )
-    .execute(&mut *tx)
-    .await?;
-
     // A folder's default rules are an ordered array, first match wins, so the rewrite has to
     // preserve their order. A rule left on the old address makes `ensure_permissioned_as_exists`
     // reject the creation of every runnable the rule matches.
diff --git a/backend/windmill-api-workspaces/src/workspaces.rs b/backend/windmill-api-workspaces/src/workspaces.rs
index 879e739dc0..f9bf9625f3 100644
--- a/backend/windmill-api-workspaces/src/workspaces.rs
+++ b/backend/windmill-api-workspaces/src/workspaces.rs
@@ -6995,10 +6995,6 @@ fn repoint_cloned_app_identity(policy: &mut serde_json::Value, authed: &ApiAuthe
         "on_behalf_of".to_string(),
         serde_json::Value::String(username_to_permissioned_as(&authed.username)),
     );
-    obj.insert(
-        "on_behalf_of_email".to_string(),
-        serde_json::Value::String(authed.email.clone()),
-    );
 }
 
 async fn clone_apps(
diff --git a/backend/windmill-api/src/offboarding.rs b/backend/windmill-api/src/offboarding.rs
index 26eb06c8e8..736b81d28f 100644
--- a/backend/windmill-api/src/offboarding.rs
+++ b/backend/windmill-api/src/offboarding.rs
@@ -957,26 +957,22 @@ async fn offboard_user_from_workspace<'c>(
     .unwrap_or(0);
 
     sqlx::query!(
-        "UPDATE app SET policy = jsonb_set(
-            jsonb_set(policy, ARRAY['on_behalf_of'], to_jsonb($1::text)),
-            ARRAY['on_behalf_of_email'], to_jsonb($4::text)
-        ) WHERE policy->>'on_behalf_of' = $2 AND workspace_id = $3",
+        "UPDATE app SET policy = jsonb_set(policy, ARRAY['on_behalf_of'], to_jsonb($1::text))
+         WHERE policy->>'on_behalf_of' = $2 AND workspace_id = $3",
         &new_permissioned_as,
         departing.as_deref(),
-        w_id,
-        new_on_behalf_of_user_email
+        w_id
     )
     .execute(&mut **tx)
     .await?;
 
     // An app draft carries a copy of the deployed policy and is deployed from it, so it needs
-    // the same pair rewritten — the draft sweep above only covers scripts and flows.
+    // the same principal rewritten — the draft sweep above only covers scripts and flows.
     sqlx::query!(
-        r#"UPDATE draft SET value = to_json(jsonb_set(jsonb_set(to_jsonb(value), ARRAY['policy', 'on_behalf_of'], to_jsonb($1::text)), ARRAY['policy', 'on_behalf_of_email'], to_jsonb($4::text))) WHERE typ IN ('app', 'raw_app') AND value->'policy'->>'on_behalf_of' = $2 AND workspace_id = $3"#,
+        r#"UPDATE draft SET value = to_json(jsonb_set(to_jsonb(value), ARRAY['policy', 'on_behalf_of'], to_jsonb($1::text))) WHERE typ IN ('app', 'raw_app') AND value->'policy'->>'on_behalf_of' = $2 AND workspace_id = $3"#,
         new_permissioned_as,
         departing.as_deref(),
-        w_id,
-        new_on_behalf_of_user_email
+        w_id
     )
     .execute(&mut **tx)
     .await?;
diff --git a/backend/windmill-api/src/users.rs b/backend/windmill-api/src/users.rs
index 4dd073b3af..1e3d3e73e6 100644
--- a/backend/windmill-api/src/users.rs
+++ b/backend/windmill-api/src/users.rs
@@ -277,18 +277,22 @@ async fn rename_user(
 
     // The per-workspace sweep below only reaches accounts with a `usr` row. A superadmin acting
     // outside their workspaces has none, yet an app can name them: their principal is
-    // `u/{password.username}`, which this rename just moved. Matching on the address as well
-    // keeps a like-named member of some other workspace out of it.
+    // `u/{password.username}`, which this rename just moved. The `NOT EXISTS` is what keeps a
+    // like-named member of some other workspace out of it — in a workspace holding that
+    // username, `resolve_username_to_email` answers from `usr` and never reaches this account,
+    // and the per-workspace sweep is what moves those rows.
     if let Some(old_username) = old_instance_username.filter(|u| *u != ru.new_username) {
         let old_principal = windmill_common::users::username_to_permissioned_as(&old_username);
-        let new_principal =
-            windmill_common::users::username_to_permissioned_as(&ru.new_username);
+        let new_principal = windmill_common::users::username_to_permissioned_as(&ru.new_username);
         sqlx::query!(
             "UPDATE app SET policy = jsonb_set(policy, ARRAY['on_behalf_of'], to_jsonb($1::text))
-             WHERE policy->>'on_behalf_of' = $2 AND policy->>'on_behalf_of_email' = $3",
+             WHERE policy->>'on_behalf_of' = $2
+               AND NOT EXISTS (
+                 SELECT 1 FROM usr WHERE usr.workspace_id = app.workspace_id AND usr.username = $3
+               )",
             &new_principal,
             &old_principal,
-            user_email
+            &old_username
         )
         .execute(&mut *tx)
         .await?;
@@ -296,10 +300,12 @@ async fn rename_user(
             r#"UPDATE draft SET value = to_json(jsonb_set(to_jsonb(value), ARRAY['policy', 'on_behalf_of'], to_jsonb($1::text)))
                WHERE typ IN ('app', 'raw_app')
                  AND value->'policy'->>'on_behalf_of' = $2
-                 AND value->'policy'->>'on_behalf_of_email' = $3"#,
+                 AND NOT EXISTS (
+                   SELECT 1 FROM usr WHERE usr.workspace_id = draft.workspace_id AND usr.username = $3
+                 )"#,
             &new_principal,
             &old_principal,
-            user_email
+            &old_username
         )
         .execute(&mut *tx)
         .await?;