diff --git a/src/core/postgres-engine.ts b/src/core/postgres-engine.ts
index 1ed51ce9a..4ad16bab4 100644
--- a/src/core/postgres-engine.ts
+++ b/src/core/postgres-engine.ts
@@ -1614,16 +1614,16 @@ export class PostgresEngine implements BrainEngine {
       params.push(symbolKind);
       symbolKindClause = `AND cc.symbol_type = $${params.length}`;
     }
-    // v0.27.0: date filtering support
+    // v0.29.1: since/until filter by effective date, with import-time fallback.
     let afterDateClause = '';
     if (opts?.afterDate) {
       params.push(opts.afterDate);
-      afterDateClause = `AND COALESCE(p.updated_at, p.created_at) > $${params.length}::timestamptz`;
+      afterDateClause = `AND COALESCE(p.effective_date, p.updated_at, p.created_at) > $${params.length}::timestamptz`;
     }
     let beforeDateClause = '';
     if (opts?.beforeDate) {
       params.push(opts.beforeDate);
-      beforeDateClause = `AND COALESCE(p.updated_at, p.created_at) < $${params.length}::timestamptz`;
+      beforeDateClause = `AND COALESCE(p.effective_date, p.updated_at, p.created_at) < $${params.length}::timestamptz`;
     }
     // v0.34.1 (#861 — P0 leak seal): source-isolation filter. When the
     // caller's auth scope is set, narrow the inner CTE candidate set so
@@ -1763,16 +1763,16 @@ export class PostgresEngine implements BrainEngine {
       params.push(symbolKind);
       symbolKindClause = `AND cc.symbol_type = $${params.length}`;
     }
-    // v0.27.0: date filtering support
+    // v0.29.1: since/until filter by effective date, with import-time fallback.
     let afterDateClause = '';
     if (opts?.afterDate) {
       params.push(opts.afterDate);
-      afterDateClause = `AND COALESCE(p.updated_at, p.created_at) > $${params.length}::timestamptz`;
+      afterDateClause = `AND COALESCE(p.effective_date, p.updated_at, p.created_at) > $${params.length}::timestamptz`;
     }
     let beforeDateClause = '';
     if (opts?.beforeDate) {
       params.push(opts.beforeDate);
-      beforeDateClause = `AND COALESCE(p.updated_at, p.created_at) < $${params.length}::timestamptz`;
+      beforeDateClause = `AND COALESCE(p.effective_date, p.updated_at, p.created_at) < $${params.length}::timestamptz`;
     }
     // v0.34.1 (#861 — P0 leak seal): source-isolation. Anchor primitive
     // for two-pass retrieval, so cross-source anchors would let the walk
@@ -1885,16 +1885,16 @@ export class PostgresEngine implements BrainEngine {
       params.push(symbolKind);
       symbolKindClause = `AND cc.symbol_type = $${params.length}`;
     }
-    // v0.27.0: date filtering support
+    // v0.29.1: since/until filter by effective date, with import-time fallback.
     let afterDateClause = '';
     if (opts?.afterDate) {
       params.push(opts.afterDate);
-      afterDateClause = `AND COALESCE(p.updated_at, p.created_at) > $${params.length}::timestamptz`;
+      afterDateClause = `AND COALESCE(p.effective_date, p.updated_at, p.created_at) > $${params.length}::timestamptz`;
     }
     let beforeDateClause = '';
     if (opts?.beforeDate) {
       params.push(opts.beforeDate);
-      beforeDateClause = `AND COALESCE(p.updated_at, p.created_at) < $${params.length}::timestamptz`;
+      beforeDateClause = `AND COALESCE(p.effective_date, p.updated_at, p.created_at) < $${params.length}::timestamptz`;
     }
     // v0.34.1 (#861, F2 — P0 leak seal): source-isolation in the INNER CTE
     // specifically. Pushing the filter inside narrows the HNSW candidate set
diff --git a/test/postgres-engine.test.ts b/test/postgres-engine.test.ts
index 0cf2afdfb..e750f9d5f 100644
--- a/test/postgres-engine.test.ts
+++ b/test/postgres-engine.test.ts
@@ -94,12 +94,30 @@ describe('postgres-engine / search path timeout isolation', () => {
   });
 });
 
+describe('postgres-engine / search date filtering', () => {
+  test('search paths filter since/until on effective_date before import-time fallback', () => {
+    const expectedDateExpr = 'COALESCE(p.effective_date, p.updated_at, p.created_at)';
+    const staleDatePredicate = /COALESCE\(p\.updated_at,\s*p\.created_at\)\s*[<>]\s*\$/;
+
+    for (const methodName of ['searchKeyword', 'searchKeywordChunks', 'searchVector']) {
+      const fn = stripComments(extractMethod(SRC, methodName));
+
+      expect(countOccurrences(fn, expectedDateExpr)).toBe(2);
+      expect(fn).not.toMatch(staleDatePredicate);
+    }
+  });
+});
+
 function stripComments(s: string): string {
   return s
     .replace(/\/\*[\s\S]*?\*\//g, '')
     .replace(/(^|\s)\/\/[^\n]*/g, '$1');
 }
 
+function countOccurrences(s: string, needle: string): number {
+  return s.split(needle).length - 1;
+}
+
 // extractMethod grabs the body of a class method by brace-matching from
 // its opening line. Returns the method body up to the matching closing
 // brace. Good enough for the small number of methods in this file.