diff --git a/RELEASENOTES-DEVELOPMENT.md b/RELEASENOTES-DEVELOPMENT.md
index d9979139..48437bfd 100644
--- a/RELEASENOTES-DEVELOPMENT.md
+++ b/RELEASENOTES-DEVELOPMENT.md
@@ -1,3 +1,8 @@
+Version 4.1-dev-815-gcb097034
+====
+**Enhancement**
+* Use [TCP `keepalive`](https://en.wikipedia.org/wiki/Keepalive) to close down a play session when the client disappears, e.g. when the player goes out of range of WiFi. A play session is now terminated after a break in connection lasting more than approximately one minute.
+
 Version 4.1-dev-809-g8a69f5ea
 ====
 **Enhancements**