diff --git a/composer.lock b/composer.lock
index 616d8d8b0b7..f84fffca97a 100644
--- a/composer.lock
+++ b/composer.lock
@@ -487,7 +487,7 @@
         },
         {
             "name": "drupal/core",
-            "version": "10.1.x-dev",
+            "version": "10.1.0-alpha1",
             "dist": {
                 "type": "path",
                 "url": "core",
@@ -644,7 +644,7 @@
         },
         {
             "name": "drupal/core-project-message",
-            "version": "10.1.x-dev",
+            "version": "10.1.0-alpha1",
             "dist": {
                 "type": "path",
                 "url": "composer/Plugin/ProjectMessage",
@@ -677,7 +677,7 @@
         },
         {
             "name": "drupal/core-vendor-hardening",
-            "version": "10.1.x-dev",
+            "version": "10.1.0-alpha1",
             "dist": {
                 "type": "path",
                 "url": "composer/Plugin/VendorHardening",
@@ -8626,11 +8626,7 @@
     ],
     "aliases": [],
     "minimum-stability": "dev",
-    "stability-flags": {
-        "drupal/core": 20,
-        "drupal/core-project-message": 20,
-        "drupal/core-vendor-hardening": 20
-    },
+    "stability-flags": [],
     "prefer-stable": true,
     "prefer-lowest": false,
     "platform": [],
diff --git a/composer/Metapackage/CoreRecommended/composer.json b/composer/Metapackage/CoreRecommended/composer.json
index 5bdeadfefdf..c23febf407b 100644
--- a/composer/Metapackage/CoreRecommended/composer.json
+++ b/composer/Metapackage/CoreRecommended/composer.json
@@ -7,7 +7,7 @@
         "webflo/drupal-core-strict": "*"
     },
     "require": {
-        "drupal/core": "10.1.x-dev",
+        "drupal/core": "10.1.0-alpha1",
         "asm89/stack-cors": "~v2.1.1",
         "composer/semver": "~3.3.2",
         "doctrine/annotations": "~1.14.3",
diff --git a/composer/Metapackage/PinnedDevDependencies/composer.json b/composer/Metapackage/PinnedDevDependencies/composer.json
index 4732a8aeeb4..a52237ab1f9 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": "10.1.x-dev",
+        "drupal/core": "10.1.0-alpha1",
         "behat/mink": "v1.10.0",
         "behat/mink-browserkit-driver": "v2.1.0",
         "behat/mink-selenium2-driver": "v1.6.0",
diff --git a/composer/Template/LegacyProject/composer.json b/composer/Template/LegacyProject/composer.json
index 7480cb6db42..28506099d25 100644
--- a/composer/Template/LegacyProject/composer.json
+++ b/composer/Template/LegacyProject/composer.json
@@ -27,7 +27,7 @@
     "conflict": {
         "drupal/drupal": "*"
     },
-    "minimum-stability": "dev",
+    "minimum-stability": "alpha",
     "prefer-stable": true,
     "config": {
         "allow-plugins": {
diff --git a/composer/Template/RecommendedProject/composer.json b/composer/Template/RecommendedProject/composer.json
index c2062229f05..f60ec191382 100644
--- a/composer/Template/RecommendedProject/composer.json
+++ b/composer/Template/RecommendedProject/composer.json
@@ -26,7 +26,7 @@
     "conflict": {
         "drupal/drupal": "*"
     },
-    "minimum-stability": "dev",
+    "minimum-stability": "alpha",
     "prefer-stable": true,
     "config": {
         "allow-plugins": {
diff --git a/core/lib/Drupal.php b/core/lib/Drupal.php
index e15df7f7ab1..0a784b865c4 100644
--- a/core/lib/Drupal.php
+++ b/core/lib/Drupal.php
@@ -75,7 +75,7 @@ class Drupal {
   /**
    * The current system version.
    */
-  const VERSION = '10.1.0-dev';
+  const VERSION = '10.1.0-alpha1';
 
   /**
    * Core API compatibility.
diff --git a/core/lib/Drupal/Component/Annotation/composer.json b/core/lib/Drupal/Component/Annotation/composer.json
index a7ddbf2b678..3eed1cce162 100644
--- a/core/lib/Drupal/Component/Annotation/composer.json
+++ b/core/lib/Drupal/Component/Annotation/composer.json
@@ -9,9 +9,9 @@
     "require": {
         "php": ">=8.1.0",
         "doctrine/annotations": "^1.14",
-        "drupal/core-file-cache": "10.1.x-dev",
-        "drupal/core-plugin": "10.1.x-dev",
-        "drupal/core-utility": "10.1.x-dev"
+        "drupal/core-file-cache": "10.1.0-alpha1",
+        "drupal/core-plugin": "10.1.0-alpha1",
+        "drupal/core-utility": "10.1.0-alpha1"
     },
     "autoload": {
         "psr-4": {
@@ -23,5 +23,5 @@
             "This file was partially generated automatically. See: https://www.drupal.org/node/3293830"
         ]
     },
-    "minimum-stability": "dev"
+    "minimum-stability": "alpha"
 }
diff --git a/core/lib/Drupal/Component/Datetime/composer.json b/core/lib/Drupal/Component/Datetime/composer.json
index 7a1429803d6..b7bb2ffc174 100644
--- a/core/lib/Drupal/Component/Datetime/composer.json
+++ b/core/lib/Drupal/Component/Datetime/composer.json
@@ -8,7 +8,7 @@
     "license": "GPL-2.0-or-later",
     "require": {
         "php": ">=8.1.0",
-        "drupal/core-utility": "10.1.x-dev"
+        "drupal/core-utility": "10.1.0-alpha1"
     },
     "autoload": {
         "psr-4": {
@@ -20,5 +20,5 @@
             "This file was partially generated automatically. See: https://www.drupal.org/node/3293830"
         ]
     },
-    "minimum-stability": "dev"
+    "minimum-stability": "alpha"
 }
diff --git a/core/lib/Drupal/Component/Discovery/composer.json b/core/lib/Drupal/Component/Discovery/composer.json
index 5d3ea3487c1..f88f271039c 100644
--- a/core/lib/Drupal/Component/Discovery/composer.json
+++ b/core/lib/Drupal/Component/Discovery/composer.json
@@ -8,8 +8,8 @@
     "license": "GPL-2.0-or-later",
     "require": {
         "php": ">=8.1.0",
-        "drupal/core-file-cache": "10.1.x-dev",
-        "drupal/core-serialization": "10.1.x-dev"
+        "drupal/core-file-cache": "10.1.0-alpha1",
+        "drupal/core-serialization": "10.1.0-alpha1"
     },
     "autoload": {
         "psr-4": {
@@ -21,5 +21,5 @@
             "This file was partially generated automatically. See: https://www.drupal.org/node/3293830"
         ]
     },
-    "minimum-stability": "dev"
+    "minimum-stability": "alpha"
 }
diff --git a/core/lib/Drupal/Component/FrontMatter/composer.json b/core/lib/Drupal/Component/FrontMatter/composer.json
index 2fc1da7a757..1de3bf6544d 100644
--- a/core/lib/Drupal/Component/FrontMatter/composer.json
+++ b/core/lib/Drupal/Component/FrontMatter/composer.json
@@ -8,7 +8,7 @@
     "license": "GPL-2.0-or-later",
     "require": {
         "php": ">=8.1.0",
-        "drupal/core-serialization": "10.1.x-dev"
+        "drupal/core-serialization": "10.1.0-alpha1"
     },
     "autoload": {
         "psr-4": {
@@ -20,5 +20,5 @@
             "This file was partially generated automatically. See: https://www.drupal.org/node/3293830"
         ]
     },
-    "minimum-stability": "dev"
+    "minimum-stability": "alpha"
 }
diff --git a/core/lib/Drupal/Component/Gettext/composer.json b/core/lib/Drupal/Component/Gettext/composer.json
index 9b6a7f3e8bb..6db4266a16a 100644
--- a/core/lib/Drupal/Component/Gettext/composer.json
+++ b/core/lib/Drupal/Component/Gettext/composer.json
@@ -9,7 +9,7 @@
     },
     "require": {
         "php": ">=8.1.0",
-        "drupal/core-render": "10.1.x-dev"
+        "drupal/core-render": "10.1.0-alpha1"
     },
     "autoload": {
         "psr-4": {
@@ -21,5 +21,5 @@
             "This file was partially generated automatically. See: https://www.drupal.org/node/3293830"
         ]
     },
-    "minimum-stability": "dev"
+    "minimum-stability": "alpha"
 }
diff --git a/core/lib/Drupal/Component/PhpStorage/composer.json b/core/lib/Drupal/Component/PhpStorage/composer.json
index 603314d00f8..a0a40563fe4 100644
--- a/core/lib/Drupal/Component/PhpStorage/composer.json
+++ b/core/lib/Drupal/Component/PhpStorage/composer.json
@@ -8,7 +8,7 @@
     "license": "GPL-2.0-or-later",
     "require": {
         "php": ">=8.1.0",
-        "drupal/core-file-security": "10.1.x-dev"
+        "drupal/core-file-security": "10.1.0-alpha1"
     },
     "autoload": {
         "psr-4": {
@@ -20,5 +20,5 @@
             "This file was partially generated automatically. See: https://www.drupal.org/node/3293830"
         ]
     },
-    "minimum-stability": "dev"
+    "minimum-stability": "alpha"
 }
diff --git a/core/lib/Drupal/Component/Render/composer.json b/core/lib/Drupal/Component/Render/composer.json
index ba1f47c04bb..88e1f43e1af 100644
--- a/core/lib/Drupal/Component/Render/composer.json
+++ b/core/lib/Drupal/Component/Render/composer.json
@@ -8,7 +8,7 @@
     "license": "GPL-2.0-or-later",
     "require": {
         "php": ">=8.1.0",
-        "drupal/core-utility": "10.1.x-dev"
+        "drupal/core-utility": "10.1.0-alpha1"
     },
     "autoload": {
         "psr-4": {
@@ -20,5 +20,5 @@
             "This file was partially generated automatically. See: https://www.drupal.org/node/3293830"
         ]
     },
-    "minimum-stability": "dev"
+    "minimum-stability": "alpha"
 }