diff --git a/composer.lock b/composer.lock
index 95b3429d55ec4ab88ab9e50ceb8de4cc90852607..03b213fc7a8bf2dde278e55308b5f1e5ae59b2a5 100644
--- a/composer.lock
+++ b/composer.lock
@@ -531,7 +531,7 @@
         },
         {
             "name": "drupal/core",
-            "version": "9.3.0-rc1",
+            "version": "9.3.x-dev",
             "dist": {
                 "type": "path",
                 "url": "core",
@@ -788,7 +788,7 @@
         },
         {
             "name": "drupal/core-project-message",
-            "version": "9.3.0-rc1",
+            "version": "9.3.x-dev",
             "dist": {
                 "type": "path",
                 "url": "composer/Plugin/ProjectMessage",
@@ -821,7 +821,7 @@
         },
         {
             "name": "drupal/core-vendor-hardening",
-            "version": "9.3.0-rc1",
+            "version": "9.3.x-dev",
             "dist": {
                 "type": "path",
                 "url": "composer/Plugin/VendorHardening",
@@ -7909,6 +7909,9 @@
     "aliases": [],
     "minimum-stability": "dev",
     "stability-flags": {
+        "drupal/core": 20,
+        "drupal/core-project-message": 20,
+        "drupal/core-vendor-hardening": 20,
         "symfony/phpunit-bridge": 10,
         "symfony/var-dumper": 10
     },
@@ -7919,5 +7922,5 @@
     "platform-overrides": {
         "php": "7.3.0"
     },
-    "plugin-api-version": "2.0.0"
+    "plugin-api-version": "2.1.0"
 }
diff --git a/composer/Metapackage/CoreRecommended/composer.json b/composer/Metapackage/CoreRecommended/composer.json
index 595630d37e8621cac86294d926eac2ab98eefe16..4bf1b955dd193bdb603b497e8373d6d92a2706c2 100644
--- a/composer/Metapackage/CoreRecommended/composer.json
+++ b/composer/Metapackage/CoreRecommended/composer.json
@@ -7,7 +7,7 @@
         "webflo/drupal-core-strict": "*"
     },
     "require": {
-        "drupal/core": "9.3.0-rc1",
+        "drupal/core": "9.3.x-dev",
         "asm89/stack-cors": "1.3.0",
         "composer/semver": "3.2.6",
         "doctrine/annotations": "1.13.2",
diff --git a/composer/Metapackage/PinnedDevDependencies/composer.json b/composer/Metapackage/PinnedDevDependencies/composer.json
index 4b8e5591393082ea9b7b475c4fb11353946e3472..56ac0a0800f8891b0698eb43ee17afd40011cea8 100644
--- a/composer/Metapackage/PinnedDevDependencies/composer.json
+++ b/composer/Metapackage/PinnedDevDependencies/composer.json
@@ -7,7 +7,7 @@
         "webflo/drupal-core-require-dev": "*"
     },
     "require": {
-        "drupal/core": "9.3.0-rc1",
+        "drupal/core": "9.3.x-dev",
         "behat/mink": "v1.9.0",
         "behat/mink-selenium2-driver": "v1.5.0",
         "composer/ca-bundle": "1.3.1",
diff --git a/composer/Template/LegacyProject/composer.json b/composer/Template/LegacyProject/composer.json
index 8a59a6c6111dbf4e6bec476a0f0a2f8c0d7b6685..1b1a2af337ab82947aadd8c0bd4a60fa65447a2c 100644
--- a/composer/Template/LegacyProject/composer.json
+++ b/composer/Template/LegacyProject/composer.json
@@ -27,7 +27,7 @@
     "conflict": {
         "drupal/drupal": "*"
     },
-    "minimum-stability": "RC",
+    "minimum-stability": "dev",
     "prefer-stable": true,
     "config": {
         "sort-packages": true
diff --git a/composer/Template/RecommendedProject/composer.json b/composer/Template/RecommendedProject/composer.json
index 33d355a4cc705a6d3bd2b54a8157d3513733b264..99e9f55f239450f5b34d4e885c73f9d6c3b4fc2d 100644
--- a/composer/Template/RecommendedProject/composer.json
+++ b/composer/Template/RecommendedProject/composer.json
@@ -26,7 +26,7 @@
     "conflict": {
         "drupal/drupal": "*"
     },
-    "minimum-stability": "RC",
+    "minimum-stability": "dev",
     "prefer-stable": true,
     "config": {
         "sort-packages": true
diff --git a/core/lib/Drupal.php b/core/lib/Drupal.php
index 02cd42e3e7dd6ec3eab2923091fa43f2decde129..5e67fbc33ab84f858741081996f16a5e378a66a0 100644
--- a/core/lib/Drupal.php
+++ b/core/lib/Drupal.php
@@ -75,7 +75,7 @@ class Drupal {
   /**
    * The current system version.
    */
-  const VERSION = '9.3.0-rc1';
+  const VERSION = '9.3.0-dev';
 
   /**
    * Core API compatibility.