diff --git a/core/build_id.mk b/core/build_id.mk
index cd68ea3..5c66d68 100644
--- a/core/build_id.mk
+++ b/core/build_id.mk
@@ -13,21 +13,9 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 #
-# BUILD_ID is of the form NPM1.YYMMDD.nnn
-#
-# N - dessert designator
-# P - vertical, or category of release
-# M1 - release abbreviation
-# YY - year
-# MM - month
-# DD - day
-# nnn - the patch sequence, starting at 001 for the initial snap
-#
-# OPAT.161221.002
-#
-# See also:
-#
-# https://docs.google.com/document/d/17eqVTxMc2do05T6qwt4eASVyxy8u3Cme4u4fVD5q0VM/view#
-#
+# BUILD_ID is usually used to specify the branch name
+# (like "MAIN") or a branch name and a release candidate
+# (like "CRB01").  It must be a single word, and is
+# capitalized by convention.
 
-export BUILD_ID=OPR6.170623.014
+export BUILD_ID=OPR2.170623.002
diff --git a/core/version_defaults.mk b/core/version_defaults.mk
index 56a4f88..c4d926a 100644
--- a/core/version_defaults.mk
+++ b/core/version_defaults.mk
@@ -165,7 +165,7 @@
     #  It must be of the form "YYYY-MM-DD" on production devices.
     #  It must match one of the Android Security Patch Level strings of the Public Security Bulletins.
     #  If there is no $PLATFORM_SECURITY_PATCH set, keep it empty.
-      PLATFORM_SECURITY_PATCH := 2017-09-05
+      PLATFORM_SECURITY_PATCH := 2017-08-05
 endif
 
 ifndef PLATFORM_BASE_OS