diff --git a/org.eclipse.xtext.tests/testdata/wizard-expectations/full/full.parent/full.target/full.target.target b/org.eclipse.xtext.tests/testdata/wizard-expectations/full/full.parent/full.target/full.target.target
index aa23c6184..43ab414b7 100644
--- a/org.eclipse.xtext.tests/testdata/wizard-expectations/full/full.parent/full.target/full.target.target
+++ b/org.eclipse.xtext.tests/testdata/wizard-expectations/full/full.parent/full.target/full.target.target
@@ -13,7 +13,7 @@
 		</location>
 		<location includeAllPlatforms="false" includeConfigurePhase="false" includeMode="planner" includeSource="true" type="InstallableUnit">
 			<unit id="org.eclipse.emf.mwe2.launcher.feature.group" version="0.0.0"/>
-			<repository location="https://download.eclipse.org/modeling/emft/mwe/updates/releases/2.12.1/"/>
+			<repository location="https://download.eclipse.org/modeling/emft/mwe/updates/milestones/S202108160852/"/>
 		</location>
 		<location includeAllPlatforms="false" includeConfigurePhase="false" includeMode="planner" includeSource="true" type="InstallableUnit">
 			<unit id="org.eclipse.xtext.sdk.feature.group" version="0.0.0"/>
diff --git a/org.eclipse.xtext.tests/testdata/wizard-expectations/full/full.parent/pom.xml b/org.eclipse.xtext.tests/testdata/wizard-expectations/full/full.parent/pom.xml
index 154b8ded5..0de25d180 100644
--- a/org.eclipse.xtext.tests/testdata/wizard-expectations/full/full.parent/pom.xml
+++ b/org.eclipse.xtext.tests/testdata/wizard-expectations/full/full.parent/pom.xml
@@ -8,7 +8,7 @@
 
 	<properties>
 		<xtextVersion>unspecified</xtextVersion>
-		<mwe2Version>2.12.1</mwe2Version>
+		<mwe2Version>2.12.2.M1</mwe2Version>
 		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
 		<maven.compiler.source>1.8</maven.compiler.source>
 		<maven.compiler.target>1.8</maven.compiler.target>
diff --git a/org.eclipse.xtext.tests/testdata/wizard-expectations/lsMavenTychoApp/lsMavenTychoApp.parent/lsMavenTychoApp.target/lsMavenTychoApp.target.target b/org.eclipse.xtext.tests/testdata/wizard-expectations/lsMavenTychoApp/lsMavenTychoApp.parent/lsMavenTychoApp.target/lsMavenTychoApp.target.target
index 87675bbdd..b044c5f6b 100644
--- a/org.eclipse.xtext.tests/testdata/wizard-expectations/lsMavenTychoApp/lsMavenTychoApp.parent/lsMavenTychoApp.target/lsMavenTychoApp.target.target
+++ b/org.eclipse.xtext.tests/testdata/wizard-expectations/lsMavenTychoApp/lsMavenTychoApp.parent/lsMavenTychoApp.target/lsMavenTychoApp.target.target
@@ -13,7 +13,7 @@
 		</location>
 		<location includeAllPlatforms="false" includeConfigurePhase="false" includeMode="planner" includeSource="true" type="InstallableUnit">
 			<unit id="org.eclipse.emf.mwe2.launcher.feature.group" version="0.0.0"/>
-			<repository location="https://download.eclipse.org/modeling/emft/mwe/updates/releases/2.12.1/"/>
+			<repository location="https://download.eclipse.org/modeling/emft/mwe/updates/milestones/S202108160852/"/>
 		</location>
 		<location includeAllPlatforms="false" includeConfigurePhase="false" includeMode="planner" includeSource="true" type="InstallableUnit">
 			<unit id="org.eclipse.xtext.sdk.feature.group" version="0.0.0"/>
diff --git a/org.eclipse.xtext.tests/testdata/wizard-expectations/lsMavenTychoApp/lsMavenTychoApp.parent/pom.xml b/org.eclipse.xtext.tests/testdata/wizard-expectations/lsMavenTychoApp/lsMavenTychoApp.parent/pom.xml
index 4bd82d287..ae9052d08 100644
--- a/org.eclipse.xtext.tests/testdata/wizard-expectations/lsMavenTychoApp/lsMavenTychoApp.parent/pom.xml
+++ b/org.eclipse.xtext.tests/testdata/wizard-expectations/lsMavenTychoApp/lsMavenTychoApp.parent/pom.xml
@@ -8,7 +8,7 @@
 
 	<properties>
 		<xtextVersion>unspecified</xtextVersion>
-		<mwe2Version>2.12.1</mwe2Version>
+		<mwe2Version>2.12.2.M1</mwe2Version>
 		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
 		<maven.compiler.source>1.8</maven.compiler.source>
 		<maven.compiler.target>1.8</maven.compiler.target>
diff --git a/org.eclipse.xtext.tests/testdata/wizard-expectations/lsMavenTychoFatjar/lsMavenTychoFatjar.parent/lsMavenTychoFatjar.target/lsMavenTychoFatjar.target.target b/org.eclipse.xtext.tests/testdata/wizard-expectations/lsMavenTychoFatjar/lsMavenTychoFatjar.parent/lsMavenTychoFatjar.target/lsMavenTychoFatjar.target.target
index 53f81cbf7..6146a08de 100644
--- a/org.eclipse.xtext.tests/testdata/wizard-expectations/lsMavenTychoFatjar/lsMavenTychoFatjar.parent/lsMavenTychoFatjar.target/lsMavenTychoFatjar.target.target
+++ b/org.eclipse.xtext.tests/testdata/wizard-expectations/lsMavenTychoFatjar/lsMavenTychoFatjar.parent/lsMavenTychoFatjar.target/lsMavenTychoFatjar.target.target
@@ -13,7 +13,7 @@
 		</location>
 		<location includeAllPlatforms="false" includeConfigurePhase="false" includeMode="planner" includeSource="true" type="InstallableUnit">
 			<unit id="org.eclipse.emf.mwe2.launcher.feature.group" version="0.0.0"/>
-			<repository location="https://download.eclipse.org/modeling/emft/mwe/updates/releases/2.12.1/"/>
+			<repository location="https://download.eclipse.org/modeling/emft/mwe/updates/milestones/S202108160852/"/>
 		</location>
 		<location includeAllPlatforms="false" includeConfigurePhase="false" includeMode="planner" includeSource="true" type="InstallableUnit">
 			<unit id="org.eclipse.xtext.sdk.feature.group" version="0.0.0"/>
diff --git a/org.eclipse.xtext.tests/testdata/wizard-expectations/lsMavenTychoFatjar/lsMavenTychoFatjar.parent/pom.xml b/org.eclipse.xtext.tests/testdata/wizard-expectations/lsMavenTychoFatjar/lsMavenTychoFatjar.parent/pom.xml
index 99ac5b1a8..26fec4236 100644
--- a/org.eclipse.xtext.tests/testdata/wizard-expectations/lsMavenTychoFatjar/lsMavenTychoFatjar.parent/pom.xml
+++ b/org.eclipse.xtext.tests/testdata/wizard-expectations/lsMavenTychoFatjar/lsMavenTychoFatjar.parent/pom.xml
@@ -8,7 +8,7 @@
 
 	<properties>
 		<xtextVersion>unspecified</xtextVersion>
-		<mwe2Version>2.12.1</mwe2Version>
+		<mwe2Version>2.12.2.M1</mwe2Version>
 		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
 		<maven.compiler.source>1.8</maven.compiler.source>
 		<maven.compiler.target>1.8</maven.compiler.target>
diff --git a/org.eclipse.xtext.tests/testdata/wizard-expectations/mavenTycho/mavenTycho.parent/mavenTycho.target/mavenTycho.target.target b/org.eclipse.xtext.tests/testdata/wizard-expectations/mavenTycho/mavenTycho.parent/mavenTycho.target/mavenTycho.target.target
index acb35e486..fd773eb49 100644
--- a/org.eclipse.xtext.tests/testdata/wizard-expectations/mavenTycho/mavenTycho.parent/mavenTycho.target/mavenTycho.target.target
+++ b/org.eclipse.xtext.tests/testdata/wizard-expectations/mavenTycho/mavenTycho.parent/mavenTycho.target/mavenTycho.target.target
@@ -13,7 +13,7 @@
 		</location>
 		<location includeAllPlatforms="false" includeConfigurePhase="false" includeMode="planner" includeSource="true" type="InstallableUnit">
 			<unit id="org.eclipse.emf.mwe2.launcher.feature.group" version="0.0.0"/>
-			<repository location="https://download.eclipse.org/modeling/emft/mwe/updates/releases/2.12.1/"/>
+			<repository location="https://download.eclipse.org/modeling/emft/mwe/updates/milestones/S202108160852/"/>
 		</location>
 		<location includeAllPlatforms="false" includeConfigurePhase="false" includeMode="planner" includeSource="true" type="InstallableUnit">
 			<unit id="org.eclipse.xtext.sdk.feature.group" version="0.0.0"/>
diff --git a/org.eclipse.xtext.tests/testdata/wizard-expectations/mavenTycho/mavenTycho.parent/pom.xml b/org.eclipse.xtext.tests/testdata/wizard-expectations/mavenTycho/mavenTycho.parent/pom.xml
index 1e4a6f845..02630012a 100644
--- a/org.eclipse.xtext.tests/testdata/wizard-expectations/mavenTycho/mavenTycho.parent/pom.xml
+++ b/org.eclipse.xtext.tests/testdata/wizard-expectations/mavenTycho/mavenTycho.parent/pom.xml
@@ -8,7 +8,7 @@
 
 	<properties>
 		<xtextVersion>unspecified</xtextVersion>
-		<mwe2Version>2.12.1</mwe2Version>
+		<mwe2Version>2.12.2.M1</mwe2Version>
 		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
 		<maven.compiler.source>1.8</maven.compiler.source>
 		<maven.compiler.target>1.8</maven.compiler.target>
diff --git a/org.eclipse.xtext.tests/testdata/wizard-expectations/mavenTychoJ11/mavenTychoJ11.parent/mavenTychoJ11.target/mavenTychoJ11.target.target b/org.eclipse.xtext.tests/testdata/wizard-expectations/mavenTychoJ11/mavenTychoJ11.parent/mavenTychoJ11.target/mavenTychoJ11.target.target
index a5078eec6..43dbaf610 100644
--- a/org.eclipse.xtext.tests/testdata/wizard-expectations/mavenTychoJ11/mavenTychoJ11.parent/mavenTychoJ11.target/mavenTychoJ11.target.target
+++ b/org.eclipse.xtext.tests/testdata/wizard-expectations/mavenTychoJ11/mavenTychoJ11.parent/mavenTychoJ11.target/mavenTychoJ11.target.target
@@ -12,7 +12,7 @@
 		</location>
 		<location includeAllPlatforms="false" includeConfigurePhase="false" includeMode="planner" includeSource="true" type="InstallableUnit">
 			<unit id="org.eclipse.emf.mwe2.launcher.feature.group" version="0.0.0"/>
-			<repository location="https://download.eclipse.org/modeling/emft/mwe/updates/releases/2.12.1/"/>
+			<repository location="https://download.eclipse.org/modeling/emft/mwe/updates/milestones/S202108160852/"/>
 		</location>
 		<location includeAllPlatforms="false" includeConfigurePhase="false" includeMode="planner" includeSource="true" type="InstallableUnit">
 			<unit id="org.eclipse.xtext.sdk.feature.group" version="0.0.0"/>
diff --git a/org.eclipse.xtext.tests/testdata/wizard-expectations/mavenTychoJ11/mavenTychoJ11.parent/pom.xml b/org.eclipse.xtext.tests/testdata/wizard-expectations/mavenTychoJ11/mavenTychoJ11.parent/pom.xml
index d3969697a..1caa02f0e 100644
--- a/org.eclipse.xtext.tests/testdata/wizard-expectations/mavenTychoJ11/mavenTychoJ11.parent/pom.xml
+++ b/org.eclipse.xtext.tests/testdata/wizard-expectations/mavenTychoJ11/mavenTychoJ11.parent/pom.xml
@@ -8,7 +8,7 @@
 
 	<properties>
 		<xtextVersion>unspecified</xtextVersion>
-		<mwe2Version>2.12.1</mwe2Version>
+		<mwe2Version>2.12.2.M1</mwe2Version>
 		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
 		<maven.compiler.source>11</maven.compiler.source>
 		<maven.compiler.target>11</maven.compiler.target>
diff --git a/org.eclipse.xtext.tests/testdata/wizard-expectations/mavenTychoP2/mavenTychoP2.parent/mavenTychoP2.target/mavenTychoP2.target.target b/org.eclipse.xtext.tests/testdata/wizard-expectations/mavenTychoP2/mavenTychoP2.parent/mavenTychoP2.target/mavenTychoP2.target.target
index a4ef00769..186e0bbef 100644
--- a/org.eclipse.xtext.tests/testdata/wizard-expectations/mavenTychoP2/mavenTychoP2.parent/mavenTychoP2.target/mavenTychoP2.target.target
+++ b/org.eclipse.xtext.tests/testdata/wizard-expectations/mavenTychoP2/mavenTychoP2.parent/mavenTychoP2.target/mavenTychoP2.target.target
@@ -13,7 +13,7 @@
 		</location>
 		<location includeAllPlatforms="false" includeConfigurePhase="false" includeMode="planner" includeSource="true" type="InstallableUnit">
 			<unit id="org.eclipse.emf.mwe2.launcher.feature.group" version="0.0.0"/>
-			<repository location="https://download.eclipse.org/modeling/emft/mwe/updates/releases/2.12.1/"/>
+			<repository location="https://download.eclipse.org/modeling/emft/mwe/updates/milestones/S202108160852/"/>
 		</location>
 		<location includeAllPlatforms="false" includeConfigurePhase="false" includeMode="planner" includeSource="true" type="InstallableUnit">
 			<unit id="org.eclipse.xtext.sdk.feature.group" version="0.0.0"/>
diff --git a/org.eclipse.xtext.tests/testdata/wizard-expectations/mavenTychoP2/mavenTychoP2.parent/pom.xml b/org.eclipse.xtext.tests/testdata/wizard-expectations/mavenTychoP2/mavenTychoP2.parent/pom.xml
index d8fca01ce..0739086fd 100644
--- a/org.eclipse.xtext.tests/testdata/wizard-expectations/mavenTychoP2/mavenTychoP2.parent/pom.xml
+++ b/org.eclipse.xtext.tests/testdata/wizard-expectations/mavenTychoP2/mavenTychoP2.parent/pom.xml
@@ -8,7 +8,7 @@
 
 	<properties>
 		<xtextVersion>unspecified</xtextVersion>
-		<mwe2Version>2.12.1</mwe2Version>
+		<mwe2Version>2.12.2.M1</mwe2Version>
 		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
 		<maven.compiler.source>1.8</maven.compiler.source>
 		<maven.compiler.target>1.8</maven.compiler.target>
diff --git a/org.eclipse.xtext.util/src/org/eclipse/xtext/util/XtextVersion.java b/org.eclipse.xtext.util/src/org/eclipse/xtext/util/XtextVersion.java
index 24e1559b7..83613561c 100644
--- a/org.eclipse.xtext.util/src/org/eclipse/xtext/util/XtextVersion.java
+++ b/org.eclipse.xtext.util/src/org/eclipse/xtext/util/XtextVersion.java
@@ -52,14 +52,14 @@ public class XtextVersion {
 	 * @noreference
 	 */
 	public String getMweVersion() {
-		return "2.12.1";
+		return "2.12.2.M1";
 	}
 	
 	/**
 	 * @noreference
 	 */
 	public String getMweBuildNumber() {
-		return "";
+		return "S202108160852";
 	}
 
 	public String getAntlrGeneratorVersion() {
diff --git a/releng/releng-target/xtext-core.target.target b/releng/releng-target/xtext-core.target.target
index 8eca2b724..f75726481 100644
--- a/releng/releng-target/xtext-core.target.target
+++ b/releng/releng-target/xtext-core.target.target
@@ -3,7 +3,7 @@
 <target name="org.eclipse.xtext.core.target" sequenceNumber="0">
 	<locations>
 		<location includeAllPlatforms="false" includeConfigurePhase="false" includeMode="planner" includeSource="true" type="InstallableUnit">
-			<repository location="https://download.eclipse.org/modeling/tmf/xtext/updates/releases/2.25.0"/>
+			<repository location="https://download.eclipse.org/modeling/tmf/xtext/updates/milestones/S202105271020/"/>
 			<unit id="org.eclipse.xtext.sdk.feature.group" version="0.0.0"/>
 		</location>
 		<location includeAllPlatforms="false" includeConfigurePhase="false" includeMode="planner" includeSource="true" type="InstallableUnit">
@@ -11,7 +11,7 @@
 			<unit id="org.eclipse.emf.sdk.feature.group" version="0.0.0"/>
 		</location>
 		<location includeAllPlatforms="false" includeConfigurePhase="false" includeMode="planner" includeSource="true" type="InstallableUnit">
-			<repository location="https://download.eclipse.org/modeling/emft/mwe/updates/releases/2.12.1/"/>
+			<repository location="https://download.eclipse.org/modeling/emft/mwe/updates/milestones/S202108160852/"/>
 			<unit id="org.eclipse.emf.mwe2.language.sdk.feature.group" version="0.0.0"/>
 		</location>
 		<location includeAllPlatforms="false" includeConfigurePhase="false" includeMode="planner" includeSource="true" type="InstallableUnit">