diff --git a/core/version_defaults.mk b/core/version_defaults.mk
index 31c3242..ea10f2a 100644
--- a/core/version_defaults.mk
+++ b/core/version_defaults.mk
@@ -53,7 +53,7 @@
   # intermediate builds).  During development, this number remains at the
   # SDK version the branch is based on and PLATFORM_VERSION_CODENAME holds
   # the code-name of the new development work.
-  PLATFORM_SDK_VERSION := 20
+  PLATFORM_SDK_VERSION := 21
 endif
 
 ifeq "" "$(PLATFORM_VERSION_CODENAME)"