Deleveraging-Flush Reversal at Moderate Frequency, Single-Venue Long-Short (Single-Instrument BTCUSDT.BINANCE USD-M — Fade a Sharp 4H Price Move That Coincides With a Fast DROP in Open Interest = Forced-Liquidation Flush; MODERATE Trigger Threshold Tuned for ~100+ Measurable Trades; Reversion Target + ATR Stop + Time Exit, 3-Parameter)

A LONG-SHORT, SINGLE-INSTRUMENT, SINGLE-VENUE event-driven reversal on BTCUSDT.BINANCE USD-M perpetual, deliberately engineered to occupy the ONE viable frequency niche the failure log now reveals: MODERATE turnover. The log shows a vise — fast strategies die fee_edge (212x), and low-turnover strategies die structural unmeasurability (my Donchian breakout died at ~47 trades vs a ~100-trade floor; sandbox produced only 4). So this targets ~150-400 trades over the sample (holds ~1 day, a few triggers per week), enough to validate while per-trade moves stay large enough to clear fees. The edge uses OPEN INTEREST — orthogonal to price, non-trend, and reliably populated on BINANCE USD-M (satisfies L42) — via a forced-deleveraging mechanism, NOT a momentum confluence (avoids the L41 0/213 clone class) and NOT a price-only reversal. Mechanism: when price moves sharply over a few hours AND open interest simultaneously DROPS fast, the move is being driven by forced liquidation / margin stop-outs closing positions (price-insensitive flow that overshoots), not fresh conviction. Once the leveraged cohort is flushed, price snaps back. Fade the flush: sharp down-move on collapsing OI → LONG (longs liquidated into a vacuum, bounce); sharp up-move on collapsing OI → SHORT (shorts squeezed out). Critically, the trigger threshold is set MODERATE (not extreme) precisely so the strategy fires often enough to be statistically measurable — directly fixing the too-few-trades death — while each flush still produces a >0.4% reversion that clears the 0.10% USD-M round trip. It is distinct from my six in-flight ideas (all low-turnover momentum/trend) by mechanism (forced-flow reversal), horizon (moderate frequency), and feed role (OI collapse as a flush detector, not a momentum confirm). Single-venue, single-instrument — no L44, no L43, BINANCE USD-M (not COIN-M, whose OI loops). 3 parameters. Instruments: ["BTCUSDT.BINANCE"]. venue_type: futures. data_requirements: ["ohlcv", "open_interest"].