diff --git a/.github/maven-release/README.md b/.github/maven-release/README.md
index 98461cba..34aa0e66 100644
--- a/.github/maven-release/README.md
+++ b/.github/maven-release/README.md
@@ -13,7 +13,8 @@ If CurseForge has accepted the file but it isn't public yet, wait for approval.
 Start a new run with the recorded CurseForge file ID so it verifies that upload
 without submitting the jar again. The release workflow sets Java 8 through
 Minecraft 1.16.5, Java 16 for Minecraft 1.17.1, Java 17 through Minecraft 1.20.1,
-and Java 21 for Minecraft 1.20.6 and 1.21.1.
+Java 21 for Minecraft 1.20.6 through 1.21.11, and Java 25 for Minecraft 26.1.2.
+Unknown version branches are rejected until their release target is reviewed.
 
 ## Existing CurseForge releases
 
diff --git a/.github/maven-release/test_verify.py b/.github/maven-release/test_verify.py
new file mode 100644
index 00000000..bfea9e1d
--- /dev/null
+++ b/.github/maven-release/test_verify.py
@@ -0,0 +1,26 @@
+import unittest
+
+import verify
+
+
+class ReleaseTargetTests(unittest.TestCase):
+    def test_released_minecraft_lines_keep_their_runtime(self):
+        for java, versions in {
+            8: ("1.10.2", "1.12.2", "1.13.2", "1.14.4", "1.15.2", "1.16.5"),
+            16: ("1.17.1",),
+            17: ("1.18.2", "1.19.4", "1.20.1"),
+            21: ("1.20.6", "1.21.1", "1.21.11"),
+            25: ("26.1.2",),
+        }.items():
+            for version in versions:
+                with self.subTest(version=version):
+                    self.assertEqual((version, f"Java {java}"), verify.release_target(f"master-{version}"))
+
+    def test_unqualified_or_malformed_targets_are_rejected(self):
+        for branch in ("master-26.2", "master-26.1.2-extra", "feature/26.1.2", "26.1.2", "master-main", "master-26.1.2\n"):
+            with self.subTest(branch=branch), self.assertRaises(ValueError):
+                verify.release_target(branch)
+
+
+if __name__ == "__main__":
+    unittest.main()
diff --git a/.github/maven-release/verify.py b/.github/maven-release/verify.py
index b7b5eebc..fda046d5 100644
--- a/.github/maven-release/verify.py
+++ b/.github/maven-release/verify.py
@@ -27,6 +27,19 @@ def digest(data):
     return hashlib.sha256(data).hexdigest()
 
 
+def release_target(branch):
+    require(branch.startswith("master-"), "Release requires a version master branch")
+    minecraft = branch.removeprefix("master-")
+    java_versions = {
+        "1.10.2": 8, "1.12.2": 8, "1.13.2": 8, "1.14.4": 8,
+        "1.15.2": 8, "1.16.5": 8, "1.17.1": 16, "1.18.2": 17,
+        "1.19.4": 17, "1.20.1": 17, "1.20.6": 21, "1.21.1": 21,
+        "1.21.11": 21, "26.1.2": 25,
+    }
+    require(minecraft in java_versions, f"Unsupported Minecraft version: {minecraft}")
+    return minecraft, f"Java {java_versions[minecraft]}"
+
+
 def read_url(url, allow_absent=False):
     if url.startswith(MAVEN + "/"):
         # The CDN can cache pre-upload 404s even with a no-cache request header.
@@ -161,7 +174,10 @@ def main():
     manifest = json.loads(MANIFEST.read_text(encoding="utf-8"))
     require(version in manifest["releases"], f"Version is not approved: {version}")
     release, work = manifest["releases"][version], Path(folder)
-    if mode in ("stage", "stage-candidate"):
+    if mode == "target":
+        minecraft, java = release_target(release["branch"])
+        print(f"minecraft={minecraft}\njava={java}")
+    elif mode in ("stage", "stage-candidate"):
         stage(manifest, version, release, work, candidate=mode == "stage-candidate")
     elif mode == "verify-curseforge":
         verify_curseforge(manifest, version, release, int(os.environ["CURSEFORGE_FILE_ID"]),
diff --git a/.github/workflows/deploy-release.yml b/.github/workflows/deploy-release.yml
index bc48f7d3..deb362b9 100644
--- a/.github/workflows/deploy-release.yml
+++ b/.github/workflows/deploy-release.yml
@@ -60,6 +60,7 @@ jobs:
           set -euo pipefail
           [[ "$RELEASE_VERSION" =~ ^[0-9]+\.[0-9]+\.[0-9]+\.[0-9]+$ ]]
           [[ -z "$EXISTING_CF_FILE" || "$EXISTING_CF_FILE" =~ ^[1-9][0-9]*$ ]]
+          python3 -m unittest discover -s .github/maven-release -p 'test_*.py'
           release_work="$RUNNER_TEMP/release"
           python3 .github/maven-release/verify.py stage-candidate "$RELEASE_VERSION" "$release_work"
           bash gradlew -p .github/maven-release generatePomFileForMavenJavaPublication \
@@ -69,19 +70,11 @@ jobs:
             echo "Maven already has this release. Supply its existing CurseForge file ID." >&2
             exit 1
           fi
-          mc=$(jq -er --arg v "$RELEASE_VERSION" '.releases[$v].branch | capture("^master-(?<mc>1\\.[0-9]+\\.[0-9]+)$").mc' .github/maven-release/releases.json)
-          case "$mc" in
-            1.10.2|1.12.2|1.13.2|1.14.4|1.15.2|1.16.5) java="Java 8" ;;
-            1.17.1) java="Java 16" ;;
-            1.18.2|1.19.4|1.20.1) java="Java 17" ;;
-            1.20.6|1.21.1|1.21.11) java="Java 21" ;;
-            *) echo "Unsupported Minecraft version for this publisher: $mc" >&2; exit 1 ;;
-          esac
-          echo "minecraft=$mc" >> "$GITHUB_OUTPUT"
-          echo "java=$java" >> "$GITHUB_OUTPUT"
+          target=$(python3 .github/maven-release/verify.py target "$RELEASE_VERSION" "$release_work")
+          printf '%s\n' "$target" >> "$GITHUB_OUTPUT"
           echo "state=$state" >> "$GITHUB_OUTPUT"
           echo "RELEASE_WORK=$release_work" >> "$GITHUB_ENV"
-          echo "Verified $RELEASE_VERSION for Minecraft $mc. Maven: $state." >> "$GITHUB_STEP_SUMMARY"
+          echo "Verified $RELEASE_VERSION. $target. Maven: $state." >> "$GITHUB_STEP_SUMMARY"
 
       - name: Check publication credentials
         if: inputs.mode == 'publish'