diff --git a/frontend/src/views/admin/ProjectDetail.test.ts b/frontend/src/views/admin/ProjectDetail.test.ts
index bbaadc9e..c40f5e6c 100644
--- a/frontend/src/views/admin/ProjectDetail.test.ts
+++ b/frontend/src/views/admin/ProjectDetail.test.ts
@@ -50,6 +50,17 @@ describe("ProjectDetail setup draft publish workflow", () => {
     expect(source.indexOf("applySetupDraft(createDefaultSetupDraft(siteOptions.value));", functionIndex)).toBe(-1);
   });
 
+  it("does not let legacy empty projectInfo overwrite project master data", () => {
+    const source = readProjectDetail();
+    const functionIndex = source.indexOf("const applySetupDraft = (draft: SetupConfigDraft) => {");
+    const emptyGuardIndex = source.indexOf("!isProjectPublishSnapshotEmpty(projectInfo) || isSetupDraftEffectivelyEmpty(setupDraft)", functionIndex);
+    const fallbackIndex = source.indexOf("setupDraft.projectInfo = buildProjectPublishSnapshot();", emptyGuardIndex);
+
+    expect(functionIndex).toBeGreaterThan(-1);
+    expect(emptyGuardIndex).toBeGreaterThan(functionIndex);
+    expect(fallbackIndex).toBeGreaterThan(emptyGuardIndex);
+  });
+
   it("keeps early termination out of regular visit schedule options", () => {
     const source = readProjectDetail();
 
diff --git a/frontend/src/views/admin/ProjectDetail.vue b/frontend/src/views/admin/ProjectDetail.vue
index 615aed33..643fa6fb 100644
--- a/frontend/src/views/admin/ProjectDetail.vue
+++ b/frontend/src/views/admin/ProjectDetail.vue
@@ -4009,6 +4009,9 @@ const isProjectPublishSnapshotShape = (value: unknown): value is ProjectPublishS
   );
 };
 
+const isProjectPublishSnapshotEmpty = (snapshot: ProjectPublishSnapshot): boolean =>
+  JSON.stringify(snapshot) === JSON.stringify(emptyProjectInfoDraft());
+
 const applyProjectInfoDraft = (snapshot: ProjectPublishSnapshot) => {
   suppressEnrollmentFieldSync.value = true;
   form.value.code = snapshot.code || "";
@@ -4044,7 +4047,11 @@ const applySetupDraft = (draft: SetupConfigDraft) => {
   setupDraft.siteEnrollmentPlans = normalizeSiteEnrollmentPlans(clone(draft.siteEnrollmentPlans));
   setupDraft.monitoringStrategies = clone(draft.monitoringStrategies);
   setupDraft.centerConfirm = clone(draft.centerConfirm);
-  applyProjectInfoDraft(projectInfo);
+  if (!isProjectPublishSnapshotEmpty(projectInfo) || isSetupDraftEffectivelyEmpty(setupDraft)) {
+    applyProjectInfoDraft(projectInfo);
+  } else {
+    setupDraft.projectInfo = buildProjectPublishSnapshot();
+  }
   formBaselineSnapshot.value = serializeFormForCompare();
   suppressDraftWatch.value = false;
 };