diff --git a/BUILD b/BUILD
index 1d5b0216526..b3a51987cdf 100644
--- a/BUILD
+++ b/BUILD
@@ -66,9 +66,9 @@ config_setting(
 # This should be updated along with build.yaml
 g_stands_for = "glamorous"
 
-core_version = "6.0.0-dev"
+core_version = "6.0.0-pre1"
 
-version = "1.10.0-dev"
+version = "1.10.0-pre1"
 
 GPR_PUBLIC_HDRS = [
     "include/grpc/support/alloc.h",
diff --git a/build.yaml b/build.yaml
index b20eba99749..63829e246f3 100644
--- a/build.yaml
+++ b/build.yaml
@@ -12,9 +12,9 @@ settings:
   '#08': Use "-preN" suffixes to identify pre-release versions
   '#09': Per-language overrides are possible with (eg) ruby_version tag here
   '#10': See the expand_version.py for all the quirks here
-  core_version: 6.0.0-dev
+  core_version: 6.0.0-pre1
   g_stands_for: glamorous
-  version: 1.10.0-dev
+  version: 1.10.0-pre1
 filegroups:
 - name: census
   public_headers: