diff --git a/frontend/packages/dashboard/src/dashboard.css b/frontend/packages/dashboard/src/dashboard.css
index a0d0e04c..dc5dd382 100644
--- a/frontend/packages/dashboard/src/dashboard.css
+++ b/frontend/packages/dashboard/src/dashboard.css
@@ -1181,6 +1181,14 @@ footer .banner-thin {
   display: inline-block;
   padding: 0 4px 1px;
 }
+/* Column for an agent no longer in the live roster — its past schedules
+   linger but the agent is gone. Greyed + struck through so the operator
+   can still see (and cancel) the stale entries rather than be surprised. */
+.schedules-table-agent-th--gone > div {
+  color: var(--muted);
+  text-decoration: line-through;
+  opacity: 0.75;
+}
 .schedules-table-row-cancelled td { opacity: 0.55; }
 .schedules-table-body-cell {
   max-width: 30em;
diff --git a/frontend/packages/dashboard/src/schedules.js b/frontend/packages/dashboard/src/schedules.js
index 7b2eabb3..b396f4d8 100644
--- a/frontend/packages/dashboard/src/schedules.js
+++ b/frontend/packages/dashboard/src/schedules.js
@@ -619,9 +619,16 @@ function renderSchedulesTableHead(agents) {
     el('th', {}, 'owner'),
     el('th', { class: 'schedules-table-body-th' }, 'body'),
   );
+  // 'operator' is always a valid target; every other column maps to a
+  // container, so flag any column whose agent is no longer in the live
+  // roster — its past schedules linger in the table but the agent is gone.
+  const liveNames = new Set(Array.from(containersState.values()).map((c) => c.name));
   for (const a of agents) {
-    headerRow.append(el('th', { class: 'schedules-table-agent-th', title: a },
-      el('div', {}, el('span', {}, a))));
+    const gone = a !== 'operator' && !liveNames.has(a);
+    headerRow.append(el('th', {
+      class: 'schedules-table-agent-th' + (gone ? ' schedules-table-agent-th--gone' : ''),
+      title: gone ? a + ' — no longer exists (gone)' : a,
+    }, el('div', {}, el('span', {}, a))));
   }
   headerRow.append(el('th', { class: 'schedules-table-actions-th' }, ''));
   thead.append(headerRow);