Add 'in development' caveat for 2.15.15 and 2.16.10

Change-Id: I9740c6b1d9841fd74f547ba9611b4c45ee84930d
diff --git a/pages/site/releases/2.15.md b/pages/site/releases/2.15.md
index 5cb586f..3d3ae74 100644
--- a/pages/site/releases/2.15.md
+++ b/pages/site/releases/2.15.md
@@ -422,7 +422,7 @@
 
 ## Bugfix Releases
 
-### 2.15.15
+### 2.15.15 (in development)
 
 * Upgrade JGit to 4.11.8.201904181247-r.
 
diff --git a/pages/site/releases/2.16.md b/pages/site/releases/2.16.md
index 5820510..484dd8c 100644
--- a/pages/site/releases/2.16.md
+++ b/pages/site/releases/2.16.md
@@ -545,7 +545,7 @@
 
 ## Bugfix Releases
 
-### 2.16.10
+### 2.16.10 (in development)
 
 * [Issue 10664](https://bugs.chromium.org/p/gerrit/issues/detail?id=10664):
 Fix duplicate key detection in MySQL patch review database.