diff --git a/handoff/NOTES_LEVEL.md b/handoff/NOTES_LEVEL.md
index 095ede6..366e00a 100644
--- a/handoff/NOTES_LEVEL.md
+++ b/handoff/NOTES_LEVEL.md
@@ -1060,3 +1060,20 @@ FULL honest 24-bit corpus (59 cases) inside ONE fixed bridge pipeline
    F1 (params of the LUT curve) is hereby CLOSED as "already produced, none accepted";
    the structural A/B/gamma from ctx+0x188 remains the only path to bytes (blocked:
    level-path object not live-captured; see F2/F5.)
+
+## ============ UPDATE 2026-08-20w: F2 STRUCTURAL WIRING TESTS — BOTH REGRESS (documented) ============
+Tested wiring the two remaining structural chain pieces onto the committed bridge
+(quick python precompute+OLA on a representative subset; honest 24-bit tone metric):
+  base    : mean|err| 0.75-0.80, max 2.1
+  FFT-conv step5 (mask *= win8193 0.5->1.0) : mean 5.22 (worse)  — masking the gain by
+     the freq window is WRONG direction; the 0x540658 window enters the FIR step, not a
+     simple gain multiply (confirms NOTES "window ~flat, adds almost nothing").
+  combine 0x5407c8 accumulator (acc += att*df+rel*df+g, df=g-acc, per-bin kRTAtt/kRTRel):
+     mean 4.68 (worse) — naive acc toward 2.36*g overd red by ~6x; the decomp combine
+     operates in the REDUCTION/exp2 domain (blend 0.8 pedestal + bigkernel exp2), NOT on
+     the fitted bridge final-gain. Mismatched domain => not a valid wiring test.
+CONCLUSION: F2 "wire combine+FFT-conv into the bridge" is rejected in naive form. The
+structural pieces belong to the exp2(mask) chain which regressed (Phase B, da63adc
+replaced it with the log-domain LUT bridge). The bridge (Pchip, 0.773) remains canonical.
+Path to bytes stays: exact A/B/gamma (blocked live), SR geom 48000/4096, bit-exact
+exp2/FFT. No code change made this session; NOTE-only.