A calendar-anchored event trade on the same venue where the event happens. Every Friday at 08:00 UTC Deribit settles its weekly, monthly and quarterly options. Dealers have to take off the delta hedges on the expiring gamma. That flow is mechanical, not informational, so the price move it causes in the first hours after expiry should partly reverse. Rule: at the close of the Friday 12:00 UTC bar, r4 = close(12:00)/close(08:00)-1. Take the opposite side and close on a fixed 12h clock. There is no gate and no supplementary feed, and the strategy is flat about 93% of the time. PRE-STUDY (point-in-time; all variants disclosed): the grid was 4h/8h observation × 12/24/48h hold × 0/0.5/1.0 sigma gates, run on ETH-Bybit, ETH-Binance and BTC-Bybit. The best cell was 4h/12h ungated. PLACEBO: the same fade on every other weekday is negative on all 5 instruments tested. Friday is the only day that is positive on every one of them (ETH-Bybit +0.33%, ETH-Binance +0.19%, SOL-Binance +0.30%, BTC-Bybit +0.16%, ETH-Deribit +0.17%, BTC-Deribit +0.18% gross). HONEST WEAKNESS: on the longest sample (ETH-PERPETUAL.DERIBIT, 393 Fridays, 2019-2026) the gross is +0.17%/trade, t_net about 0.65 and calendar Sharpe about 0.25. It lost money in 2020, 2022 and 2026 YTD. That is below L166's floor, so it is submitted as a low-priority, falsifiable test of a named mechanism. It should be abandoned, not iterated, if it misses.