diff --git a/includes/class-tmdo-hivepress-transient-filter.php b/includes/class-tmdo-hivepress-transient-filter.php
index 85a681a..c5a0f44 100644
--- a/includes/class-tmdo-hivepress-transient-filter.php
+++ b/includes/class-tmdo-hivepress-transient-filter.php
@@ -80,8 +80,8 @@ final class TMDO_Hivepress_Transient_Filter {
 	/** Object cache group used instead of wp_options when a persistent cache is present. */
 	public const CACHE_GROUP = 'tmdo_hp_transient';
 
-	/** Longest an object-cache entry lives: a week (HivePress's default is a day). */
-	public const MAX_CACHE_TTL = 604800;
+	/** Longest an object-cache entry lives: a day, HivePress's own default (2.4 PR-120). */
+	public const MAX_CACHE_TTL = DAY_IN_SECONDS;
 
 	/**
 	 * Register the four metadata filters on `init`. Idempotent — safe to call
diff --git a/tests/integration/HivepressTransientFilterTest.php b/tests/integration/HivepressTransientFilterTest.php
index ada423f..92fae91 100644
--- a/tests/integration/HivepressTransientFilterTest.php
+++ b/tests/integration/HivepressTransientFilterTest.php
@@ -215,11 +215,14 @@ class HivepressTransientFilterTest extends TestCase {
 
 	/**
 	 * Entries expire in the object cache too (2.3 PR-099): the value (written
-	 * first, before its timeout is known) after a week, the timeout after the
+	 * first, before its timeout is known) after a day, the timeout after the
 	 * later of that and its own time, plus a minute. Orphans of deleted posts
 	 * no longer pile up.
 	 */
 	public function test_with_an_object_cache_entries_get_a_ttl(): void {
+		// A day, HivePress's own default: at a week, 1.3M listings kept 4.7M
+		// entries (1 GB) in a shared Redis and pushed other sites' keys out (2.4 PR-120).
+		$this->assertSame( 86400, WPDO_Hivepress_Transient_Filter::MAX_CACHE_TTL );
 		$GLOBALS['_wp_using_ext_object_cache'] = true;
 		$key        = '_transient_hp_models/cat/v1';
 		$translated = WPDO_Hivepress_Transient_Filter::translate_key( 100, $key );