diff --git a/src/resources/extensions/sf/sf-db/sf-db-core.js b/src/resources/extensions/sf/sf-db/sf-db-core.js
index b86a2dc4b..acdb4553a 100644
--- a/src/resources/extensions/sf/sf-db/sf-db-core.js
+++ b/src/resources/extensions/sf/sf-db/sf-db-core.js
@@ -556,6 +556,7 @@ export function insertMilestoneSpecIfAbsent(milestoneId, planning = {}) {
 		":created_at": new Date().toISOString(),
 	};
 	if (existing) {
+		const { ":created_at": _createdAt, ...updateParams } = params;
 		currentDb
 			.prepare(`UPDATE milestone_specs SET
 	      vision = :vision,
@@ -572,7 +573,7 @@ export function insertMilestoneSpecIfAbsent(milestoneId, planning = {}) {
 	      vision_meeting_json = :vision_meeting_json,
 	      product_research_json = :product_research_json
 	     WHERE id = :id`)
-			.run(params);
+			.run(updateParams);
 		return;
 	}
 	currentDb
diff --git a/src/resources/extensions/sf/tests/spec-tables-live-planning.test.mjs b/src/resources/extensions/sf/tests/spec-tables-live-planning.test.mjs
index 39f5b8531..250424164 100644
--- a/src/resources/extensions/sf/tests/spec-tables-live-planning.test.mjs
+++ b/src/resources/extensions/sf/tests/spec-tables-live-planning.test.mjs
@@ -164,6 +164,26 @@ test("specTables_when_shell_milestone_created_before_planning_captures_first_rea
 	);
 });
 
+test("specTables_when_empty_milestone_spec_exists_upsert_replaces_without_unused_created_at_parameter", () => {
+	openDatabase(":memory:");
+
+	insertMilestone({
+		id: "M004",
+		title: "Shell first",
+		status: "active",
+	});
+	upsertMilestonePlanning("M004", {
+		vision: "First real planning payload",
+		successCriteria: ["first criterion"],
+	});
+
+	const milestoneSpec = getMilestoneSpec("M004");
+	assert.equal(milestoneSpec.vision, "First real planning payload");
+	assert.deepEqual(JSON.parse(milestoneSpec.success_criteria), [
+		"first criterion",
+	]);
+});
+
 test("specTables_when_shell_task_created_before_planning_captures_first_real_plan", () => {
 	openDatabase(":memory:");