diff --git a/build/version.ps1 b/build/version.ps1
index 303163a0c..305e90dd9 100644
--- a/build/version.ps1
+++ b/build/version.ps1
@@ -1 +1 @@
-$AntlrVersion = "4.2.2-dev"
+$AntlrVersion = "4.2.2-alpha001"
diff --git a/runtime/CSharp/Antlr4.Runtime/Properties/AssemblyInfo.cs b/runtime/CSharp/Antlr4.Runtime/Properties/AssemblyInfo.cs
index ffd421f17..4fc22707f 100644
--- a/runtime/CSharp/Antlr4.Runtime/Properties/AssemblyInfo.cs
+++ b/runtime/CSharp/Antlr4.Runtime/Properties/AssemblyInfo.cs
@@ -80,5 +80,5 @@ using System.Runtime.InteropServices;
 [assembly: AssemblyVersion("4.2.0.0")]
 #if !NET_CF
 [assembly: AssemblyFileVersion("4.2.2.0")]
-[assembly: AssemblyInformationalVersion("4.2.2-dev")]
+[assembly: AssemblyInformationalVersion("4.2.2-alpha001")]
 #endif
diff --git a/runtime/CSharp/Antlr4BuildTasks/Properties/AssemblyInfo.cs b/runtime/CSharp/Antlr4BuildTasks/Properties/AssemblyInfo.cs
index 2d1d62a0b..0cc203f4c 100644
--- a/runtime/CSharp/Antlr4BuildTasks/Properties/AssemblyInfo.cs
+++ b/runtime/CSharp/Antlr4BuildTasks/Properties/AssemblyInfo.cs
@@ -70,4 +70,4 @@ using System.Runtime.InteropServices;
 // [assembly: AssemblyVersion("1.0.*")]
 [assembly: AssemblyVersion("4.2.0.0")]
 [assembly: AssemblyFileVersion("4.2.2.0")]
-[assembly: AssemblyInformationalVersion("4.2.2-dev")]
+[assembly: AssemblyInformationalVersion("4.2.2-alpha001")]