diff --git a/runs/frontier-fidelity-envelope-v1/fixed-pd-pressure-matching-card.md b/runs/frontier-fidelity-envelope-v1/fixed-pd-pressure-matching-card.md
index 220cb9a..6b2ec07 100644
--- a/runs/frontier-fidelity-envelope-v1/fixed-pd-pressure-matching-card.md
+++ b/runs/frontier-fidelity-envelope-v1/fixed-pd-pressure-matching-card.md
@@ -31,7 +31,9 @@ The probe fixes Qwen3-30B-A3B BF16, community vLLM 0.20.0, H20, TP4, MNS64,
 MBT=8192, chunked prefill, and prefix caching off. It compares per-GPU rates
 `{1, 2, 3, 4}` (global TP4 rates `{4, 8, 12, 16}` request/s). Every rate has
 257 exact `4096 -> 256` requests in each of three fresh-server trials; rate
-orders are rotated across trials.
+orders are rotated across trials. The launcher reuses the validated vLLM 0.20
+FlashInfer kernel cache; this avoids including one-off custom-kernel JIT in
+server startup and does not alter request latency measurement.
 
 ## Decision rule
 
diff --git a/runs/frontier-fidelity-envelope-v1/run_qwen30_fixed_pd_pressure_probe.sh b/runs/frontier-fidelity-envelope-v1/run_qwen30_fixed_pd_pressure_probe.sh
index 85aed68..c1b4623 100644
--- a/runs/frontier-fidelity-envelope-v1/run_qwen30_fixed_pd_pressure_probe.sh
+++ b/runs/frontier-fidelity-envelope-v1/run_qwen30_fixed_pd_pressure_probe.sh
@@ -11,7 +11,10 @@ RUNNER_DIR="${RUNNER_DIR:-$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)}"
 CLIENT="${CLIENT:-${RUNNER_DIR}/../frontier-phase-factorial-v0/qwen30_prefill_client.py}"
 VENV_ROOT="${VENV_ROOT:-/tmp/wjh/venvs/vllm-0.20.0-cu129-profiler-v1}"
 MODEL_ROOT="${MODEL_ROOT:-/home/admin/cpfs/wjh/models/Qwen/Qwen3-30B-A3B}"
-FLASHINFER_WORKSPACE_BASE="${FLASHINFER_WORKSPACE_BASE:-${OUT}/flashinfer-workspace}"
+# Reuse the validated vLLM 0.20 H20 kernel cache. A per-output workspace
+# starts costly FlashInfer MoE JIT compilation and changes startup behavior
+# without changing the serving configuration being profiled.
+FLASHINFER_WORKSPACE_BASE="${FLASHINFER_WORKSPACE_BASE:-/tmp/wjh/flashinfer-workspace-vllm020-profiler-v1}"
 GPU_IDS="${GPU_IDS:-0,1,2,3}"
 TP="${TP:-4}"
 MNS="${MNS:-64}"
@@ -211,6 +214,7 @@ PY
   "${VENV_ROOT}/bin/vllm" --version > "${OUT}/provenance/vllm.version"
   "${VENV_ROOT}/bin/python" -c 'import torch, transformers, vllm; print(f"torch={torch.__version__}"); print(f"transformers={transformers.__version__}"); print(f"vllm={vllm.__version__}")' > "${OUT}/provenance/runtime.versions"
   ulimit -n > "${OUT}/provenance/open-file-limit"
+  readlink -f "${FLASHINFER_WORKSPACE_BASE}" > "${OUT}/provenance/flashinfer-workspace"
   nvidia-smi --query-gpu=index,name,uuid,driver_version,memory.total --format=csv,noheader > "${OUT}/provenance/gpus.before.csv"
 
   declare -a ORDERS=("4 8 12 16" "16 12 8 4" "8 16 4 12")