diff --git a/Mustang-CLI/pom.xml b/Mustang-CLI/pom.xml
index 57342dae..9ff36fae 100644
--- a/Mustang-CLI/pom.xml
+++ b/Mustang-CLI/pom.xml
@@ -3,14 +3,14 @@
 <parent>
     <groupId>org.mustangproject</groupId>
     <artifactId>core</artifactId>
-    <version>2.0.0-alpha3</version>
+    <version>2.0.0-alpha4-SNAPSHOT</version>
 </parent>
    <modelVersion>4.0.0</modelVersion>
    <groupId>org.zugferd</groupId>
    <artifactId>Mustang-CLI</artifactId>
    <name>Mustang commandline tool</name>
    <packaging>jar</packaging>
-   <version>2.0.0-alpha3</version>
+   <version>2.0.0-alpha4-SNAPSHOT</version>
    <repositories>
       <repository>
          <!-- for jargs -->
@@ -31,7 +31,7 @@
       <dependency>
          <groupId>org.mustangproject</groupId>
          <artifactId>validator</artifactId>
-         <version>2.0.0-alpha3</version>
+         <version>2.0.0-alpha4-SNAPSHOT</version>
          <!-- prototypes of new mustangproject versions can be installed by referring to them and installed to the local repo from a jar file with
         mvn install:install-file -Dfile=mustang-1.5.4-SNAPSHOT.jar -DgroupId=org.mustangproject.ZUGFeRD -DartifactId=mustang -Dversion=1.5.4 -Dpackaging=jar -DgeneratePom=true
         -->
diff --git a/library/pom.xml b/library/pom.xml
index f1ba8256..9fd80339 100644
--- a/library/pom.xml
+++ b/library/pom.xml
@@ -3,13 +3,13 @@
 <parent>
     <groupId>org.mustangproject</groupId>
     <artifactId>core</artifactId>
-    <version>2.0.0-alpha3</version>
+    <version>2.0.0-alpha4-SNAPSHOT</version>
 </parent>
 
 	<modelVersion>4.0.0</modelVersion>
 	<groupId>org.mustangproject</groupId>
 	<artifactId>library</artifactId>
-	<version>2.0.0-alpha3</version>
+	<version>2.0.0-alpha4-SNAPSHOT</version>
 	<packaging>jar</packaging>
 	<name>Library to write and read FacturX and ZUGFeRD e-invoices.  </name>
 	<description>The Mustang project is a java library to read and write ZUGFeRD meta data inside your invoice PDFs. To write files, a provided PDF/A will be combined with generated or provided XML.
@@ -19,7 +19,7 @@
 		<connection>scm:git:https://github.com/ZUGFeRD/mustangproject.git</connection>
 		<developerConnection>scm:git:https://github.com/ZUGFeRD/mustangproject.git</developerConnection>
 		<url>https://github.com/ZUGFeRD/mustangproject</url>
-		<tag>core-2.0.0-alpha3</tag>
+		<tag>mustang-2.0.0-SNAPSHOT</tag>
 	</scm>
 	<repositories>
 		<repository><!-- for jargs -->
diff --git a/pom.xml b/pom.xml
index 0446d660..359888b9 100644
--- a/pom.xml
+++ b/pom.xml
@@ -3,7 +3,7 @@
     <modelVersion>4.0.0</modelVersion>
     <groupId>org.mustangproject</groupId>
     <artifactId>core</artifactId>
-    <version>2.0.0-alpha3</version>
+    <version>2.0.0-alpha4-SNAPSHOT</version>
     <packaging>pom</packaging>
     <name>Mustang</name>
 
@@ -20,7 +20,7 @@
         <connection>scm:git:git://github.com/dexecutor/dependent-tasks-executor.git</connection>
         <developerConnection>scm:git:git@github.com:dexecutor/dexecutor.git</developerConnection>
         <url>https://github.com/dexecutor/dependent-tasks-executor</url>
-      <tag>core-2.0.0-alpha3</tag>
+      <tag>HEAD</tag>
   </scm>
     <build>
         <pluginManagement>
diff --git a/validator/pom.xml b/validator/pom.xml
index f7b2bfeb..4d7b5320 100644
--- a/validator/pom.xml
+++ b/validator/pom.xml
@@ -3,7 +3,7 @@
     <parent>
         <groupId>org.mustangproject</groupId>
         <artifactId>core</artifactId>
-        <version>2.0.0-alpha3</version>
+        <version>2.0.0-alpha4-SNAPSHOT</version>
     </parent>
     <modelVersion>4.0.0</modelVersion>
     <groupId>org.mustangproject</groupId>
@@ -11,7 +11,7 @@
     <name>Library to validate e-invoices (ZUGFeRD, Factur-X and Xrechnung)</name>
 
     <packaging>jar</packaging>
-    <version>2.0.0-alpha3</version>
+    <version>2.0.0-alpha4-SNAPSHOT</version>
     <repositories>
         <repository>
             <!-- for jargs -->
@@ -75,7 +75,7 @@
         <dependency>
             <groupId>org.mustangproject</groupId>
             <artifactId>library</artifactId>
-            <version>2.0.0-alpha3</version>
+            <version>2.0.0-alpha4-SNAPSHOT</version>
             <!-- prototypes of new mustangproject versions can be installed by referring to them and installed to the local repo from a jar file with
            mvn install:install-file -Dfile=mustang-1.5.4-SNAPSHOT.jar -DgroupId=org.mustangproject.ZUGFeRD -DartifactId=mustang -Dversion=1.5.4 -Dpackaging=jar -DgeneratePom=true
            -->