diff --git a/external_full.xml b/external_full.xml
index 4c2b9ff..3f4966a 100644
--- a/external_full.xml
+++ b/external_full.xml
@@ -21,7 +21,7 @@
   <remote  name="cos"
            fetch="https://cos.googlesource.com"
            review="https://cos-review.googlesource.com"  />
-  <default remote="cos" revision="refs/heads/master" sync-j="8" />
+  <default remote="cos" revision="refs/heads/release-R97" sync-j="8" />
   <notice>
 Your sources have been sync'd successfully.
   </notice>
@@ -66,48 +66,41 @@
 
   <!-- COS sources -->
   <project path="src/overlays"
-           name="cos/overlays/board-overlays" />
+           name="cos/overlays/board-overlays"
+           revision="refs/heads/main-R97" />
   <project path="src/third_party/portage-stable"
-           name="third_party/overlays/portage-stable" />
+           name="third_party/overlays/portage-stable"
+           revision="refs/heads/main-R97" />
   <project path="src/third_party/eclass-overlay"
            name="third_party/overlays/eclass-overlay" />
   <project path="src/third_party/chromiumos-overlay"
            sync-c="true"
-           name="third_party/overlays/chromiumos-overlay" />
+           name="third_party/overlays/chromiumos-overlay"
+           revision="refs/heads/main-R97" />
   <project path="src/scripts"
-           name="third_party/platform/crosutils"
-           revision="refs/heads/main" />
+           name="third_party/platform/crosutils" />
   <project path="chromite"
-           name="third_party/chromite"
-           revision="refs/heads/main" />
+           name="third_party/chromite" />
   <project path="src/platform/vboot_reference"
-           name="third_party/platform/vboot_reference"
-           revision="refs/heads/main" />
+           name="third_party/platform/vboot_reference" />
   <project path="src/compliance"
-           name="cos/compliance"
-           revision="refs/heads/main" />
+           name="cos/compliance" />
   <project path="src/repohooks"
-           name="cos/repohooks" />
+           name="cos/repohooks"
+           revision="refs/heads/master" />
+
   <project path="src/platform/cobble"
            name="cos/cobble" />
   <project path="manifest" name="cos/manifest" >
       <copyfile src="LICENSE" dest="LICENSE" />
   </project>
   <project path="src/third_party/policymanager"
-           name="cos/policymanager"
-           revision="refs/heads/main" />
+           name="cos/policymanager" />
   <project path="src/third_party/toolbox"
-           name="third_party/toolbox"
-           revision="refs/heads/main" />
-  <project path="src/third_party/kernel/v5.4"
-           name="third_party/kernel"
-           revision="refs/heads/cos-5.4" />
+           name="third_party/toolbox" />
   <project path="src/third_party/kernel/v5.10"
            name="third_party/kernel"
-           revision="refs/heads/cos-5.10" />
-  <project path="src/third_party/kernel/v5.15"
-           name="third_party/kernel"
-           revision="refs/heads/cos-5.15" />
+           revision="refs/heads/release-R97-cos-5.10" />
 
   <repo-hooks enabled-list="pre-upload"
            in-project="cos/repohooks" />