diff --git a/src/domain/work-orders/api/work-orders-api.ts b/src/domain/work-orders/api/work-orders-api.ts
index 03778ad3..fb02637a 100644
--- a/src/domain/work-orders/api/work-orders-api.ts
+++ b/src/domain/work-orders/api/work-orders-api.ts
@@ -370,7 +370,7 @@ export const workOrdersApi = {
       payload,
     ),
 
-  /** SH-379: manual POC override — same row/error contract as the board patch. */
+  /** Manual POC override — same row/error contract as the board patch. */
   updatePoc: async (
     id: string | number,
     payload: WorkOrderPocPatchPayload,
diff --git a/src/domain/work-orders/mappers/work-order-board-patch-mapper.ts b/src/domain/work-orders/mappers/work-order-board-patch-mapper.ts
index a24d011e..65a5dc02 100644
--- a/src/domain/work-orders/mappers/work-order-board-patch-mapper.ts
+++ b/src/domain/work-orders/mappers/work-order-board-patch-mapper.ts
@@ -50,12 +50,12 @@ export function isLocalOnlyTablePatch(patch: WorkOrderTablePatch): boolean {
   return keys.length > 0 && keys.every((key) => LOCAL_ONLY_KEYS.has(key));
 }
 
-/** SH-379: composite manual POC override op routed to PATCH …/poc. */
+/** Composite manual POC override op routed to PATCH …/poc. */
 export type BoardPocOp = {
   kind: "poc";
-  pocName: string;
-  pocPhone: string;
-  pocNotes: string;
+  pocName?: string;
+  pocPhone?: string;
+  pocNotes?: string;
 };
 
 export type BoardOp = BoardFieldOp | BoardPocOp;
@@ -70,9 +70,9 @@ function expandPocOp(patch: WorkOrderTablePatch): BoardPocOp[] {
   return [
     {
       kind: "poc",
-      pocName: patch.pocName ?? "",
-      pocPhone: patch.pocPhone ?? "",
-      pocNotes: patch.pocNotes ?? "",
+      pocName: patch.pocName,
+      pocPhone: patch.pocPhone,
+      pocNotes: patch.pocNotes,
     },
   ];
 }
diff --git a/src/domain/work-orders/types/work-order-board.ts b/src/domain/work-orders/types/work-order-board.ts
index 3bd6f067..3b06e4fb 100644
--- a/src/domain/work-orders/types/work-order-board.ts
+++ b/src/domain/work-orders/types/work-order-board.ts
@@ -134,7 +134,7 @@ export interface WorkOrderBoardPatchPayload {
   primaryDispatchId?: number | null;
 }
 
-/** Payload for PATCH /workorders/{id}/poc (SH-379 manual POC override). */
+/** Payload for PATCH /workorders/{id}/poc (manual POC override). */
 export interface WorkOrderPocPatchPayload {
   pocName: string;
   pocPhone: string;
diff --git a/src/domain/work-orders/use-cases/use-work-order-table-mutations.ts b/src/domain/work-orders/use-cases/use-work-order-table-mutations.ts
index 60b200c4..f7684958 100644
--- a/src/domain/work-orders/use-cases/use-work-order-table-mutations.ts
+++ b/src/domain/work-orders/use-cases/use-work-order-table-mutations.ts
@@ -54,19 +54,23 @@ export type WorkOrderTablePatchHandlers = {
 type PatchResult =
   { kind: "local"; patch: WorkOrderTablePatch } | { kind: "board"; row: WorkOrderTableRow };
 
+function isPocOp(op: BoardOp): op is Extract<BoardOp, { kind: "poc" }> {
+  return "kind" in op && op.kind === "poc";
+}
+
 async function applyBoardOp(
   id: string | number,
   op: BoardOp,
   row: WorkOrderTableRow,
 ): Promise<WorkOrderTableRow> {
-  if ("pocName" in op) {
+  if (isPocOp(op)) {
     if (!row.rowVersion) {
       throw new Error("workOrderVersion is required for board patch");
     }
     return workOrdersApi.updatePoc(id, {
-      pocName: op.pocName,
-      pocPhone: op.pocPhone,
-      pocNotes: op.pocNotes,
+      pocName: op.pocName ?? row.pocName,
+      pocPhone: op.pocPhone ?? row.pocPhone,
+      pocNotes: op.pocNotes ?? row.pocNotes,
       workOrderVersion: row.rowVersion,
     });
   }
diff --git a/src/domain/work-orders/utils/slide-over-draft.ts b/src/domain/work-orders/utils/slide-over-draft.ts
index 5a8bf237..7135bd01 100644
--- a/src/domain/work-orders/utils/slide-over-draft.ts
+++ b/src/domain/work-orders/utils/slide-over-draft.ts
@@ -7,7 +7,7 @@ import type {
 /**
  * Fields compared for dirty state and included in Save patch.
  * Only keys that map to board PATCH (or required companions like dispatcherName).
- * Primary POC scalars persist via the dedicated POC endpoint (SH-379);
+ * Primary POC scalars persist via the dedicated POC endpoint;
  * tech phone is not board-editable — exclude so Save cannot no-op.
  * additionalContacts is board-editable (SH-218 PATCH field).
  */
diff --git a/src/test/domain/work-orders/mappers/work-order-board-patch-mapper.test.ts b/src/test/domain/work-orders/mappers/work-order-board-patch-mapper.test.ts
index e7ebd9b0..ab852413 100644
--- a/src/test/domain/work-orders/mappers/work-order-board-patch-mapper.test.ts
+++ b/src/test/domain/work-orders/mappers/work-order-board-patch-mapper.test.ts
@@ -35,7 +35,7 @@ describe("isLocalOnlyTablePatch", () => {
     expect(isLocalOnlyTablePatch({ scheduleEnd: "2026-06-12", schedMode: "range" })).toBe(true);
   });
 
-  it("does not treat POC edits as local-only (SH-379)", () => {
+  it("does not treat POC edits as local-only", () => {
     expect(isLocalOnlyTablePatch({ pocName: "Pat", pocPhone: "111", pocNotes: "call" })).toBe(
       false,
     );
@@ -202,7 +202,7 @@ describe("expandTablePatchToBoardFieldOps", () => {
     ]);
   });
 
-  it("emits one composite POC op before scalar ops (SH-379)", () => {
+  it("emits one composite POC op before scalar ops", () => {
     expect(
       expandTablePatchToBoardFieldOps({
         pocName: "Pat",
@@ -213,7 +213,7 @@ describe("expandTablePatchToBoardFieldOps", () => {
       {
         kind: "poc",
         pocName: "Pat",
-        pocPhone: "",
+        pocPhone: undefined,
         pocNotes: "call first",
       },
       { field: "docStatus", value: "Yes" },
diff --git a/src/test/domain/work-orders/use-cases/use-work-order-table-mutations.test.tsx b/src/test/domain/work-orders/use-cases/use-work-order-table-mutations.test.tsx
index 97f364b5..a2a6798c 100644
--- a/src/test/domain/work-orders/use-cases/use-work-order-table-mutations.test.tsx
+++ b/src/test/domain/work-orders/use-cases/use-work-order-table-mutations.test.tsx
@@ -9,12 +9,14 @@ import type {
 
 const getById = vi.fn();
 const update = vi.fn();
+const updatePoc = vi.fn();
 const patchBoardField = vi.fn();
 
 vi.mock("@/domain/work-orders/api/work-orders-api", () => ({
   workOrdersApi: {
     getById: (...args: unknown[]) => getById(...args),
     update: (...args: unknown[]) => update(...args),
+    updatePoc: (...args: unknown[]) => updatePoc(...args),
     patchBoardField: (...args: unknown[]) => patchBoardField(...args),
   },
 }));
@@ -121,6 +123,7 @@ describe("useWorkOrderTableMutations completion-doc persistence", () => {
   beforeEach(() => {
     getById.mockReset();
     update.mockReset();
+    updatePoc.mockReset();
     patchBoardField.mockReset();
     serverState = { ...BASE_SERVER };
     rowState = { ...BASE_ROW };
@@ -829,6 +832,40 @@ describe("useWorkOrderTableMutations type and severity", () => {
   });
 });
 
+describe("useWorkOrderTableMutations POC persistence", () => {
+  it("fills omitted POC fields from the current row before the full replacement", async () => {
+    const currentRow = {
+      ...BASE_ROW,
+      pocName: "Alex",
+      pocPhone: "555-0000",
+      pocNotes: "Gate",
+    };
+    updatePoc.mockResolvedValue({ ...currentRow, pocName: "Jordan", rowVersion: "wo-v2" });
+
+    const { result } = renderHook(
+      () =>
+        useWorkOrderTableMutations({
+          onPatch: vi.fn(),
+          clearPatch: () => undefined,
+          getRow: () => currentRow,
+        }),
+      { wrapper: makeWrapper() },
+    );
+
+    act(() => {
+      result.current.patchField(42, { pocName: "Jordan" });
+    });
+
+    await waitFor(() => expect(updatePoc).toHaveBeenCalled());
+    expect(updatePoc).toHaveBeenCalledWith(42, {
+      pocName: "Jordan",
+      pocPhone: "555-0000",
+      pocNotes: "Gate",
+      workOrderVersion: "AAAAAAA=",
+    });
+  });
+});
+
 describe("useWorkOrderTableMutations audit cache refresh", () => {
   it("invalidates work-order queries after a successful status transition", async () => {
     const client = new QueryClient({
diff --git a/src/test/domain/work-orders/utils/slide-over-draft.test.ts b/src/test/domain/work-orders/utils/slide-over-draft.test.ts
index 322391af..2bc85efc 100644
--- a/src/test/domain/work-orders/utils/slide-over-draft.test.ts
+++ b/src/test/domain/work-orders/utils/slide-over-draft.test.ts
@@ -87,7 +87,7 @@ describe("slide-over-draft", () => {
     expect(buildSlideOverPatch(vendorDraft, row)).toEqual({ vendorId: "v2" });
   });
 
-  it("tracks POC edits for dirty state and patch (SH-379)", () => {
+  it("tracks POC edits for dirty state and patch", () => {
     const row = baseRow();
     const draft = baseRow({ pocName: "Jordan", pocPhone: "555-0100" });
     expect(isSlideOverDraftDirty(draft, row)).toBe(true);