diff --git a/.github/workflows/runner-full-stack-e2e.yml b/.github/workflows/runner-full-stack-e2e.yml
index 5c144c5339..632f5c2a74 100644
--- a/.github/workflows/runner-full-stack-e2e.yml
+++ b/.github/workflows/runner-full-stack-e2e.yml
@@ -95,7 +95,7 @@ jobs:
           AWS_PAID_RUNNER_ENABLED: ${{ vars.RUNNER_E2E_AWS_ENABLED }}
         run: |
           set -euo pipefail
-          github_runner='ubuntu-latest-m'
+          github_runner='ubuntu-latest'
           aws_runner='runs-on/fleet=paperclip-public-pr-x64/env=public-ci'
 
           if [ "$AWS_PAID_RUNNER_ENABLED" = true ]; then
@@ -111,7 +111,7 @@ jobs:
               echo "max_parallel_default=32"
               echo "max_parallel_limit=57"
             } >> "$GITHUB_OUTPUT"
-            echo '::notice title=Paid runner routing::RUNNER_E2E_AWS_ENABLED is not true; using the existing paid runner'
+            echo '::notice title=Paid runner routing::RUNNER_E2E_AWS_ENABLED is not true; using the proven GitHub-hosted runner'
           fi
 
   catalog:
diff --git a/tests/runner-e2e/README.md b/tests/runner-e2e/README.md
index c7d9cb1320..b66c7da8fe 100644
--- a/tests/runner-e2e/README.md
+++ b/tests/runner-e2e/README.md
@@ -288,8 +288,8 @@ by the repository variable `RUNNER_FULL_STACK_E2E_NIGHTLY_ENABLED=true`. Set it
 only after the live acceptance ladder in the architecture plan is green.
 Set `RUNNER_E2E_AWS_ENABLED=true` to route paid cells to the repository-scoped
 ephemeral AWS RunsOn fleet selected by
-`runs-on/fleet=paperclip-public-pr-x64/env=public-ci`. Any other value retains
-the existing `ubuntu-latest-m` target. Set `RUNNER_E2E_MAX_PARALLEL` to an
+`runs-on/fleet=paperclip-public-pr-x64/env=public-ci`. Any other value uses the
+proven GitHub-hosted `ubuntu-latest` target. Set `RUNNER_E2E_MAX_PARALLEL` to an
 integer from 1–100 on AWS (default 100); use at least 71 to run the current
 complete catalog in one wave. The fallback runner retains its 1–57 limit and
 default of 32. Multi-turn steps are sequential inside their cell while
diff --git a/tests/runner-e2e/SECURITY.md b/tests/runner-e2e/SECURITY.md
index 19f407bb76..d23deff204 100644
--- a/tests/runner-e2e/SECURITY.md
+++ b/tests/runner-e2e/SECURITY.md
@@ -67,9 +67,10 @@ the actor gate, environment branch restriction, and protected default branch.
 When `RUNNER_E2E_AWS_ENABLED=true`, paid matrix cells use the exact RunsOn fleet
 selector `runs-on/fleet=paperclip-public-pr-x64/env=public-ci`, matching the AWS
 fleet selected by `pr-trusted.yml` only after its stable numeric-ID trust gate.
-Any other or missing toggle value falls back to the existing `ubuntu-latest-m`
-paid runner and its lower concurrency ceiling. The workflow chooses between
-those two reviewed literal labels; it never evaluates a configured runner label.
+Any other or missing toggle value falls back to the GitHub-hosted
+`ubuntu-latest` runner and its lower concurrency ceiling. The workflow chooses
+between those two reviewed literal labels; it never evaluates a configured
+runner label.
 
 Keep both runner targets restricted to `paperclipai/paperclip` and workflows
 that independently authorize trusted source revisions. Never let a fork or
diff --git a/tests/runner-e2e/workflow-security.test.ts b/tests/runner-e2e/workflow-security.test.ts
index 8359b70448..fd685b597a 100644
--- a/tests/runner-e2e/workflow-security.test.ts
+++ b/tests/runner-e2e/workflow-security.test.ts
@@ -71,7 +71,7 @@ describe("public repository paid workflow security", () => {
     expect(authorizeJob).toContain(
       "aws_runner='runs-on/fleet=paperclip-public-pr-x64/env=public-ci'",
     );
-    expect(authorizeJob).toContain("github_runner='ubuntu-latest-m'");
+    expect(authorizeJob).toContain("github_runner='ubuntu-latest'");
     expect(authorizeJob).toContain(
       "AWS_PAID_RUNNER_ENABLED: ${{ vars.RUNNER_E2E_AWS_ENABLED }}",
     );