diff --git a/internal/check-packet-charts.mjs b/internal/check-packet-charts.mjs
index 9d268f3dd..e96094e73 100644
--- a/internal/check-packet-charts.mjs
+++ b/internal/check-packet-charts.mjs
@@ -12,7 +12,7 @@ import { readFileSync } from 'node:fs'
 import { fileURLToPath } from 'node:url'
 import { dirname, join } from 'node:path'
 import {
-  assertNested, assertOnePublisher, bracketSpan, fractionFromPercent, overlayPlacement, scatterCells, scatterSpread, overlayCaption, cellCount, shareCells, peoplePerCell, shareOfLists,
+  anchorPlacement, assertNested, assertOnePublisher, bracketSpan, fractionFromPercent, overlayPlacement, scatterCells, scatterSpread, overlayCaption, cellCount, shareCells, peoplePerCell, shareOfLists,
 } from '../library/components/charts/packetCharts.js'
 
 const DATA = join(dirname(fileURLToPath(import.meta.url)), '..', 'data', 'people-groups')
@@ -159,6 +159,26 @@ ok(sorted.slice(0, 5).join(',') === '139,140,221,399,418' && sorted[sorted.lengt
 ok(scatterCells(5200, 99999, 'x').size === 5200 && scatterCells(5200, -5, 'x').size === 0,
   'and the count is clamped both ways rather than throwing on a page mid-print')
 
+// ── an anchor that cannot be drawn is NAMED, not dropped (same class as the bracket) ────────────
+// ★ FOUND BY SWEEPING FOR THE CLASS, not by waiting for a second report. After the Infinity bracket
+// I read the other two templates asking the same question — what does this expression do with an
+// edge-case input? LifeCalendar matched its anchor with only an isFinite guard, so week 6000 on a
+// 5,200-cell grid, a negative week, or a fractional one matched NO cell and drew nothing. On paper
+// that is indistinguishable from having chosen not to mark it, which is the packet's own reason for
+// leaving the anchor un-defaulted in the first place — so the silent version quietly tells the
+// reader the opposite of what a missing anchor is supposed to mean.
+const TOTAL_CELLS = cellCount(100, 52)
+ok(anchorPlacement({ week: 0 }, TOTAL_CELLS).index === 0, 'week 0 is drawable — the first cell')
+ok(anchorPlacement({ week: 5199 }, TOTAL_CELLS).index === 5199, 'and the last cell is 5,199, not 5,200')
+ok(anchorPlacement({ week: 5200 }, TOTAL_CELLS).reason === 'out-of-range',
+  'week 5,200 is one past the end and says so rather than drawing nothing')
+ok(anchorPlacement({ week: -1 }, TOTAL_CELLS).reason === 'out-of-range', 'a negative week is named')
+ok(anchorPlacement({ week: 1.5 }, TOTAL_CELLS).reason === 'not-a-whole-week', 'a fractional week is named')
+ok(anchorPlacement({ week: 'soon' }, TOTAL_CELLS).reason === 'not-a-number', 'a non-numeric week is named')
+// The deliberate case must stay SILENT: no anchor asked for is not an error, it is the default.
+ok(anchorPlacement(null, TOTAL_CELLS).reason === null && anchorPlacement({}, TOTAL_CELLS).reason === null,
+  'and NO anchor at all reports nothing — the packet supplies none on purpose, so that is not a fault')
+
 // ── "1 of K lists", where K is unsettled and this asserts nothing about it ──────────────────────
 ok(shareOfLists(1, 27).percent.toFixed(2) === '3.70' && shareOfLists(1, 29).percent.toFixed(2) === '3.45',
   'K is a prop: 27 and 29 both compute, and this check takes no side on DECISION-SHEET row 41')
diff --git a/library/components/charts/LifeCalendar.vue b/library/components/charts/LifeCalendar.vue
index d946f4931..c6315e5f3 100644
--- a/library/components/charts/LifeCalendar.vue
+++ b/library/components/charts/LifeCalendar.vue
@@ -11,7 +11,7 @@
  * the component and which from the renderer.
  */
 import { computed } from 'vue'
-import { cellCount, scatterCells } from './packetCharts.js'
+import { anchorPlacement, cellCount, scatterCells } from './packetCharts.js'
 
 const props = defineProps({
   rows: { type: Number, default: 100 },
@@ -32,7 +32,8 @@ const props = defineProps({
 
 const total = computed(() => cellCount(props.rows, props.columns))
 const shadedSet = computed(() => (props.shaded > 0 ? scatterCells(total.value, props.shaded, props.seed) : new Set()))
-const anchorIndex = computed(() => (props.anchor && Number.isFinite(Number(props.anchor.week)) ? Number(props.anchor.week) : -1))
+const placedAnchor = computed(() => anchorPlacement(props.anchor, total.value))
+const anchorIndex = computed(() => placedAnchor.value.index)
 </script>
 
 <template>
@@ -52,7 +53,12 @@ const anchorIndex = computed(() => (props.anchor && Number.isFinite(Number(props
         :class="{ 'lcal__c--on': shadedSet.has(i - 1), 'lcal__c--anchor': anchorIndex === i - 1 }"
       />
     </div>
-    <p v-if="anchor && anchor.label" class="lcal__foot">{{ anchor.label }}</p>
+    <p v-if="anchor && anchor.label && anchorIndex >= 0" class="lcal__foot">{{ anchor.label }}</p>
+    <!-- An anchor that cannot be drawn is NAMED. Omitting it silently is indistinguishable, on
+         paper, from having chosen not to mark it. -->
+    <p v-else-if="placedAnchor.reason" class="lcal__unplaced" role="alert">
+      {{ labels.anchorUnplaced || 'anchor week not drawn' }}: {{ anchor.week }} ({{ placedAnchor.reason }}, grid is {{ total }} weeks)
+    </p>
     <p v-if="labels.foot" class="lcal__foot">{{ labels.foot }}</p>
   </figure>
 </template>
@@ -66,5 +72,6 @@ const anchorIndex = computed(() => (props.anchor && Number.isFinite(Number(props
 .lcal__c--on { background: var(--pk-on, #2f6d4f); border-color: var(--pk-on, #2f6d4f); }
 /* The anchor is a RING, never a fill: it marks a position without claiming the cell's meaning. */
 .lcal__c--anchor { border-color: var(--pk-ink, #1b1a17); border-width: 2px; }
+.lcal__unplaced { font: 700 12px Georgia, serif; color: #8a1c1c; margin: 6px 0 0; }
 @media print { .lcal__c { print-color-adjust: exact; -webkit-print-color-adjust: exact; } }
 </style>
diff --git a/library/components/charts/packetCharts.js b/library/components/charts/packetCharts.js
index 88944cf71..ae9ff2fd6 100644
--- a/library/components/charts/packetCharts.js
+++ b/library/components/charts/packetCharts.js
@@ -255,6 +255,27 @@ export function scatterSpread(picked, columns) {
   return { cells: picked.size, rows: rows.size }
 }
 
+/**
+ * Where an anchor week sits in the grid, or a reason it does not.
+ *
+ * ★ SAME SILENT-DROP CLASS AS THE FUNNEL'S INFINITY BRACKET, found by sweeping for it rather than
+ * waiting for it. The component matched the anchor by comparing a cell index to Number(anchor.week)
+ * with only an isFinite guard, so week 6000 on a 5,200-cell grid, a negative week, or a fractional
+ * one matched NO cell and drew nothing — the anchor the caller asked for simply was not there, with
+ * no error and no gap. On a printed page that is indistinguishable from "we chose not to mark it".
+ *
+ * Returns { index } when it can be drawn, or { index: -1, reason } when it cannot, so the component
+ * can say so instead of silently omitting it.
+ */
+export function anchorPlacement(anchor, total) {
+  if (!anchor || anchor.week == null) return { index: -1, reason: null }   // no anchor asked for
+  const w = Number(anchor.week)
+  if (!Number.isFinite(w)) return { index: -1, reason: 'not-a-number' }
+  if (!Number.isInteger(w)) return { index: -1, reason: 'not-a-whole-week' }
+  if (w < 0 || w >= (Number(total) || 0)) return { index: -1, reason: 'out-of-range' }
+  return { index: w, reason: null }
+}
+
 /** People per cell, for the caption the brief asks for explicitly. */
 export function peoplePerCell(population, rows, columns) {
   const total = cellCount(rows, columns)