diff --git a/core/envsetup.mk b/core/envsetup.mk
index 3e19198..f5a2022 100644
--- a/core/envsetup.mk
+++ b/core/envsetup.mk
@@ -66,7 +66,7 @@
   $(if $(filter $(ALL_VERSIONS),$(2)),,
     $(error Invalid MAX_PLATFORM_VERSION '$(2)'))
   $(if $(filter $(ALL_VERSIONS),$(3)),,
-    $(error Invalid DEFAULT_PLATFORM_VERSION '$(3)'))
+    $(error Invalid RELEASE_PLATFORM_VERSION '$(3)'))
 
   $(eval allowed_versions_ := $(call find_and_earlier,$(ALL_VERSIONS),$(2)))
 
@@ -77,7 +77,7 @@
     $(filter-out $(call find_and_earlier,$(allowed_versions_),$(1)),$(allowed_versions_)))
 
   $(if $(filter $(allowed_versions_),$(3)),,
-    $(error DEFAULT_PLATFORM_VERSION '$(3)' must be between MIN_PLATFORM_VERSION '$(1)' and MAX_PLATFORM_VERSION '$(2)'))
+    $(error RELEASE_PLATFORM_VERSION '$(3)' must be between MIN_PLATFORM_VERSION '$(1)' and MAX_PLATFORM_VERSION '$(2)'))
 
   $(allowed_versions_))
 endef
diff --git a/core/version_defaults.mk b/core/version_defaults.mk
index 4d1e3df..69e7051 100644
--- a/core/version_defaults.mk
+++ b/core/version_defaults.mk
@@ -40,8 +40,7 @@
   include $(INTERNAL_BUILD_ID_MAKEFILE)
 endif
 
-DEFAULT_PLATFORM_VERSION := VP1A
-.KATI_READONLY := DEFAULT_PLATFORM_VERSION
+# Set release configuration. The default resides in build/release/build_flags.mk.
 MIN_PLATFORM_VERSION := UP1A
 MAX_PLATFORM_VERSION := VP1A
 
diff --git a/core/version_util.mk b/core/version_util.mk
index 604c260..f37f2d7 100644
--- a/core/version_util.mk
+++ b/core/version_util.mk
@@ -14,17 +14,17 @@
 # limitations under the License.
 #
 
-#
-
 ALLOWED_VERSIONS := $(call allowed-platform-versions,\
   $(MIN_PLATFORM_VERSION),\
   $(MAX_PLATFORM_VERSION),\
-  $(DEFAULT_PLATFORM_VERSION))
+  $(RELEASE_PLATFORM_VERSION))
 
-ifndef TARGET_PLATFORM_VERSION
-  TARGET_PLATFORM_VERSION := $(DEFAULT_PLATFORM_VERSION)
+ifdef TARGET_PLATFORM_VERSION
+  $(error Do not set TARGET_PLATFORM_VERSION directly. Use RELEASE_PLATFORM_VERSION. value: $(TARGET_PLATFORM_VERSION))
 endif
 
+TARGET_PLATFORM_VERSION := $(RELEASE_PLATFORM_VERSION)
+
 ifeq (,$(filter $(ALLOWED_VERSIONS), $(TARGET_PLATFORM_VERSION)))
   $(warning Invalid TARGET_PLATFORM_VERSION '$(TARGET_PLATFORM_VERSION)', must be one of)
   $(error $(ALLOWED_VERSIONS))