diff --git a/docs/CHANGELOG.md b/docs/CHANGELOG.md
index 46683302..e036c90c 100644
--- a/docs/CHANGELOG.md
+++ b/docs/CHANGELOG.md
@@ -19,7 +19,10 @@
   atomically on their first structural edit or through **Optimize plans**;
   Resize, Undo/Redo and repeated edits preserve the same identities without
   accumulating off-grid coordinates. The backend Optimize transaction also
-  enforces this upgrade when invoked directly. Ambiguous legacy geometry is
+  enforces this upgrade when invoked directly. An authored wall chain remains
+  valid when it becomes a room or independent walls, while a rejected
+  transaction stores no partial result and no longer reports false success.
+  Ambiguous legacy geometry is
   left unchanged with a recovery prompt. No Plan editor controls or
   zero-thickness-wall behaviour changed
   ([#282](https://github.com/Matysh/houseplan-card/issues/282)).
diff --git a/docs/CHANGELOG.ru.md b/docs/CHANGELOG.ru.md
index 899c1601..23165d03 100755
--- a/docs/CHANGELOG.ru.md
+++ b/docs/CHANGELOG.ru.md
@@ -24,7 +24,9 @@
   изменении или через **«Оптимизировать планы»**; Resize, отмена/повтор и
   последующие правки сохраняют те же ID без накопления координат вне сетки;
   серверная транзакция Optimize также гарантирует это обновление при прямом
-  вызове.
+  вызове. Принятая пользователем цепочка остаётся допустимой при преобразовании
+  в комнату или независимые стены, а отклонённая транзакция не записывает
+  частичный результат и не показывает ложное сообщение об успехе.
   Неоднозначная старая геометрия остаётся без изменений с подсказкой по
   восстановлению. Кнопки редактора плана и поведение стен нулевой толщины не
   менялись
diff --git a/src/houseplan-card.ts b/src/houseplan-card.ts
index 7c96054f..ef32adaa 100755
--- a/src/houseplan-card.ts
+++ b/src/houseplan-card.ts
@@ -7353,7 +7353,15 @@ class HouseplanCard extends LitElement {
     let safe = false;
     try {
       const afterSpace = committedCandidate.spaces.find((space: any) => space.id === before.spaceId);
-      safe = wallModelOffGridValueCount(afterSpace) <= wallModelOffGridValueCount(historyBefore)
+      // A completed point of the active, grid-snapped chain is authored input,
+      // even before its first draft record exists in `before`. Include that
+      // transient carrier in the growth baseline; later conversion from draft
+      // to room/partition must not count the same coordinate as newly derived.
+      const authoredPoints = this._path.length >= 2
+        ? this._path.map((point) => [point[0] / NORM_W, point[1] / NORM_W])
+        : [];
+      safe = wallModelOffGridValueCount(afterSpace)
+        <= wallModelOffGridValueCount(historyBefore, authoredPoints)
         && this._checkSpacePhysicalGeometry(committedCandidate, before.spaceId).ok;
     } catch {
       safe = false;
@@ -13692,7 +13700,7 @@ class HouseplanCard extends LitElement {
       else delete sp.walls;
     }
 
-    this._commitPhysicalGeometry(this._t('history.wall_face_batch'), before);
+    if (!this._commitPhysicalGeometry(this._t('history.wall_face_batch'), before)) return;
     delete this._resumeDraftBySpace[this._space];
     this._path = [];
     this._activeDraftId = null;
diff --git a/src/wall-segment-model.ts b/src/wall-segment-model.ts
index c1f0e133..e4444675 100644
--- a/src/wall-segment-model.ts
+++ b/src/wall-segment-model.ts
@@ -80,7 +80,9 @@ const canonicalSpan = (a: number[], b: number[]): [Point, Point] => (
 const lengthOf = (a: number[], b: number[]): number => Math.hypot(b[0] - a[0], b[1] - a[1]);
 
 /** Unique authored/derived contour coordinates that are materially off-grid. */
-export const wallModelOffGridValueCount = (space: any): number => {
+export const wallModelOffGridValueCount = (
+  space: any, additionalPoints: readonly (readonly number[])[] = [],
+): number => {
   const values = new Set<string>();
   const inspect = (value: unknown): void => {
     const number = Number(value);
@@ -101,6 +103,9 @@ export const wallModelOffGridValueCount = (space: any): number => {
       inspect(segment?.b?.[0]); inspect(segment?.b?.[1]);
     }
   }
+  for (const additionalPoint of additionalPoints) {
+    inspect(additionalPoint?.[0]); inspect(additionalPoint?.[1]);
+  }
   return values.size;
 };
 const projectT = (p: number[], a: number[], b: number[]): number => {
diff --git a/test/wall-segment-model.test.mjs b/test/wall-segment-model.test.mjs
index e63acc0e..18379d92 100644
--- a/test/wall-segment-model.test.mjs
+++ b/test/wall-segment-model.test.mjs
@@ -144,6 +144,11 @@ test('off-grid contour guard counts values once across compatibility projections
     wall_segments: [{ id: 'wall', a: [point, 0], b: [point, 1], cm: 20 }],
     walls: [{ key: 'legacy', a: [point, 0], b: [point, 1], cm: 20 }],
   }), 1);
+  assert.equal(
+    wallModelOffGridValueCount({ rooms: [] }, [[point, 0], [point, 1]]),
+    1,
+    'a transient authored path contributes its coordinates to the baseline once',
+  );
 });
 
 test('room openings acquire a stable wall host while partition hosts stay untouched', () => {