diff --git a/CHANGELOG.md b/CHANGELOG.md
index 637f76c7..b5a0fde4 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -172,6 +172,8 @@ per-file diff commands.
   against the upstream repo (https and ssh forms, optional `.git` suffix), and an
   undeterminable checkout assumes upstream. Tests only, no `framework_version` bump.
 
+- **Upstream companion commands retain the selected refs** (#591) - generated follow-up commands now preserve custom base and head references instead of silently comparing the defaults.
+
 - **`linkedin-search` and `freehire-search` reject invalid `--format` flags with `BAD_ARG`** (#555,
   `.agents/skills/linkedin-search/cli/src/cli.ts`, `.agents/skills/freehire-search/cli/src/cli.ts`) -
   unrecognized `--format` flags previously fell back silently to `"json"` with exit code 0, masking
diff --git a/tests/test_upstream_crossrefs.py b/tests/test_upstream_crossrefs.py
new file mode 100644
index 00000000..c7d1fe75
--- /dev/null
+++ b/tests/test_upstream_crossrefs.py
@@ -0,0 +1,67 @@
+"""Companion commands must inspect the same selected upstream ref."""
+import re
+import shlex
+import shutil
+import subprocess
+import sys
+import unittest
+from pathlib import Path
+
+from tests.test_check_upstream_updates import UpstreamCheckerRepoFixture, FRONTMATTER
+
+
+class CompanionRefTests(UpstreamCheckerRepoFixture):
+    branch_name = "release/next"
+
+    def setUp(self):
+        super().setUp()
+        source = Path(__file__).resolve().parent.parent
+        shutil.copy(source / "tools/upstream_triage.py", self.root / "tools/upstream_triage.py")
+        self.remote = "forks/template"
+        self.branch = self.branch_name
+        # A local remote permits the real companion CLI's normal fetch without
+        # contacting a service. The selected branch differs from master.
+        self.add_remote(self.remote, str(self.root))
+        self.git("update-ref", f"refs/remotes/{self.remote}/master", "HEAD")
+        agents = self.root / "AGENTS.md"
+        agents.write_text(FRONTMATTER.replace("1.0.0", "2.0.0"), encoding="utf-8")
+        self.git("add", "AGENTS.md")
+        self.git("commit", "-qm", "update next-release methodology")
+        self.git("branch", self.branch)
+        self.git("update-ref", f"refs/remotes/{self.remote}/{self.branch}", "HEAD")
+        self.git("reset", "--hard", "HEAD~1")
+
+    def git(self, *args):
+        return subprocess.run(["git", *args], cwd=self.root, check=True, capture_output=True)
+
+    def follow(self, command):
+        argv = shlex.split(command)
+        argv[0] = sys.executable
+        result = subprocess.run(argv, cwd=self.root, capture_output=True, text=True, encoding="utf-8")
+        self.assertEqual(result.returncode, 0, result.stdout + result.stderr)
+        return result.stdout
+
+    def test_version_checker_companion_uses_selected_remote_and_branch(self):
+        result = self.run_checker("--remote", self.remote, "--branch", self.branch)
+        self.assertEqual(result.returncode, 0, result.stderr)
+        self.assertIn("[UPDATE]", result.stdout)
+        command = result.stdout.split("run: ", 1)[1].strip()
+        companion = self.follow(command)
+        self.assertIn(f"{self.remote}/{self.branch}", companion)
+        self.assertIn("**1** worth reviewing", companion)
+
+    def test_triage_companion_uses_selected_remote_and_branch(self):
+        result = subprocess.run(
+            [sys.executable, "tools/upstream_triage.py", "--remote", self.remote, "--branch", self.branch],
+            cwd=self.root, capture_output=True, text=True, encoding="utf-8",
+        )
+        self.assertEqual(result.returncode, 0, result.stderr)
+        self.assertIn("**1** worth reviewing", result.stdout)
+        command = re.search(r"run `(python tools/check_upstream_updates.py [^`]+)`", result.stdout).group(1)
+        companion = self.follow(command)
+        self.assertIn(f"{self.remote}/{self.branch}", companion)
+        self.assertIn("[UPDATE]", companion)
+
+
+class QuotedCompanionRefTests(CompanionRefTests):
+    branch_name = "release'next"
diff --git a/tools/check_upstream_updates.py b/tools/check_upstream_updates.py
index d5271546..4dd8c9db 100755
--- a/tools/check_upstream_updates.py
+++ b/tools/check_upstream_updates.py
@@ -15,6 +15,7 @@ from __future__ import annotations
 import argparse
 import os
 import re
+import shlex
 import subprocess
 import sys
 from pathlib import Path
@@ -189,7 +190,7 @@ def main() -> int:
     # answers "which upstream commits deserve review". Point at the companion.
     print(
         f"\nFor commit-level triage of upstream commits, run: "
-        f"python3 tools/upstream_triage.py --remote {remote}"
+        f"python3 tools/upstream_triage.py --remote {shlex.quote(remote)} --branch {shlex.quote(args.branch)}"
     )
     return 0
 
diff --git a/tools/upstream_triage.py b/tools/upstream_triage.py
index 4de0f800..986de66e 100755
--- a/tools/upstream_triage.py
+++ b/tools/upstream_triage.py
@@ -33,6 +33,7 @@ the upstream ref is unavailable, so a scheduled job degrades gracefully.
 from __future__ import annotations
 
 import argparse
+import shlex
 import subprocess
 import sys
 
@@ -149,7 +150,7 @@ def main() -> int:
     behind = rev_list(f"HEAD..{ref}")
     if not behind:
         print(f"Up to date with `{ref}`. Nothing to review. :white_check_mark:")
-        _print_crossref(ref)
+        _print_crossref(args.remote, args.branch)
         return 0
 
     fork_only = rev_list(f"{ref}..HEAD")
@@ -235,15 +236,15 @@ def main() -> int:
         lines.append("_None._")
 
     print("\n".join(lines))
-    _print_crossref(ref)
+    _print_crossref(args.remote, args.branch)
     return 0
 
 
-def _print_crossref(ref: str) -> None:
+def _print_crossref(remote: str, branch: str) -> None:
     print()
     print(
         "_For personalized-file version stamps (which methodology files changed), "
-        f"run `python tools/check_upstream_updates.py --remote {ref.split('/')[0]}`._"
+        f"run `python tools/check_upstream_updates.py --remote {shlex.quote(remote)} --branch {shlex.quote(branch)}`._"
     )