diff --git a/matrix/account-data/im.nheko.event_expiry/README.md b/matrix/account-data/im.nheko.event_expiry/README.md
index 3ab75e3..262747a 100644
--- a/matrix/account-data/im.nheko.event_expiry/README.md
+++ b/matrix/account-data/im.nheko.event_expiry/README.md
@@ -5,6 +5,7 @@
 <!-- START doctoc generated TOC please keep comment here to allow auto update -->
 <!-- DON'T EDIT THIS SECTION, INSTEAD RE-RUN doctoc TO UPDATE -->
 
+- [28 days](#28-days)
 - [31 days](#31-days)
 - [365 days](#365-days)
 
@@ -12,6 +13,17 @@
 
 <!-- prettier-ignore-end -->
 
+## 28 days
+
+_Also known as 4 weeks._
+
+```json
+{
+  "exclude_state_events": true,
+  "expire_after_ms": 2419200000
+}
+```
+
 ## 31 days
 
 ```json