Strike Distance Condition
How OptionsApp's Strike Distance Condition works, where to use it, and what our 1,492-spread SPX replay says about settings, backups, and risk.
An underlying-price condition that OptionsApp joins with an individual short option's price stop using AND; both conditions must be true before the REL closing order is eligible.
It changes when an order may act, not how the order fills. REL Offset, REL Limit, spread width, liquidity, and broker routing still determine execution after the gate opens.
OptionsApp is separate software that we do not build or control. This guide is based on its released feature documentation, which remains the source of truth for current product behaviour.
Cashflow Engine exports do not silently activate this condition. Configure and verify it inside OptionsApp after import, beginning on paper or in shadow mode.
What problem does it address?
The feature is designed for an option-price stop that fires while the underlying has not made a matching move toward the short strike. This can happen in a thin far-out-of-the-money option when quotes or spreads dislocate.
A price-only stop can react to an extreme option quote even when SPX is still far from the strike. The new condition adds an underlying plausibility check. For a short put, SPX must fall to the threshold; for a short call, SPX must rise to it.
| Gate | Short put | Short call |
|---|---|---|
| Option gate | Short option reaches its stop price | Short option reaches its stop price |
| Underlying gate | SPX is at or below the threshold | SPX is at or above the threshold |
| Close eligibility | Both gates must be true | Both gates must be true |
A short-put example using OptionsApp's published calculation. Prices are illustrative.
Original Cashflow Engine diagram based on the mechanics in OptionsApp's feature documentation.
A blocked order leaves the position open. When the underlying gate eventually opens, the option may be more expensive and the market may be less liquid. The condition can therefore avoid a bad print, delay a necessary stop, or do nothing during a genuine fast market.
Where can we use it?
Use it only on an individual short put or short call that has both a stop loss and Use REL enabled. OptionsApp does not expose it for long legs, combo stops, or a stop attached to an entire leg group.
The strongest use case is a far-out-of-the-money SPX 0DTE short leg whose option price can become discontinuous while SPX remains far from the strike. That maps to the separate call-side and put-side credit-spread templates generated by Cashflow Engine, provided the action is attached to the supported short leg.
It is a weaker fit when:
- the short option entered for more than about $3.50;
- the market is already moving rapidly toward or through the strike;
- a combo-level stop is required;
- OptionsApp and TWS cannot stay continuously connected; or
- there is no hard backup exit for a gate that never becomes true.
How is the threshold calculated?
Once per minute, OptionsApp converts the option stop price into a cheaper reference price, finds the closest option strike, measures its distance from SPX, smooths that distance, applies a minimum, and transfers the result to the actual short strike.
- Reference price: option stop price × Factor.
- Reference strike: same-expiry, same-right strike whose option price is closest to the reference price.
- Raw distance: distance from current SPX to that reference strike.
- Smoothed distance: median of the most recent configured one-minute readings.
- Final distance: the larger of the smoothed value and Min. distance.
- Threshold: short strike + final distance for a put, or short strike − final distance for a call.
OptionsApp updates the TWS condition when the calculated threshold changes. The app must remain connected. A disconnect can leave the last transmitted threshold in place while the market moves.
What do the settings actually do?
| Parameter | Lower value | Higher value |
|---|---|---|
| Factor | Cheaper reference option, generally farther strike, earlier/weaker gate | More expensive reference option, generally nearer strike, later/stronger gate |
| Min. distance | Lets SPX come closer before eligibility; stronger filter | Allows eligibility farther from the strike; weaker filter |
| Median over | Adapts faster and follows chain noise more closely | Smoother but slower; strength is not monotonic |
Factor must be below 1 and is currently capped by OptionsApp at 0.95. The published example—Factor 0.50, Min. distance 10, Median 5—is an illustration, not a universal optimum.
Worked short-put example
Assume a 6500 short put, a $5.00 option stop, Factor 0.50, Min. distance 10, and a five-minute median. The reference price is $2.50. If the closest reference strike is 6535 while SPX is 6560, the raw distance is 25 points. The final distance is max(25, 10) = 25, so the underlying threshold is 6500 + 25 = 6525.
The REL close may act only when the short put is at or above $5.00 and SPX is at or below 6525.
What did our historical replays find?
We ran two complementary tests. A 325-event study isolates exact short-leg stops. A strategy-level study includes all 1,492 exact spreads—including positions whose price-only stop never fired—and compares 64 settings with eight backup policies. Neither study supports a live default.
Strategy-level result
The price-only OFF control is compared with every combination of Factor .35, .50, .65 and .80; Min. distance 5, 10, 15 and 25; Median 1, 3, 5 and 10; and eight backup policies. The short exits at the displayed one-second ask and the long wing remains to official settlement. This is a declared execution scenario, not a reconstructed REL fill.
| Gate / backup | Mean delta vs OFF | Non-stress discovery | July validation | Known stress dates | Blocked-stop p95 delay |
|---|---|---|---|---|---|
| .35 / 25 / 1 — no backup | −$8.21 | $0.00 | $0.00 | −$278.41 | 19s |
| .50 / 10 / 5 — no backup | +$6.43 | −$1.69 | −$0.09 | +$257.05 | 50.8s |
| .50 / 10 / 5 — 15-second backup | −$14.50 | −$0.81 | +$0.17 | −$475.23 | 15s |
| .50 / 10 / 5 — 15:55 cutoff | +$9.20 | −$0.38 | −$0.09 | +$321.36 | 3,198s |
The positive full-sample results come from the already-known 18 May stress event. They do not repeat in discovery and validation. A 15-second timer caps a long delay but performs worse during dislocated quotes because the forced exit still occurs inside the stress tape. A 15:55 cutoff avoids the specific late-day 5 August delay, but it can leave earlier stops blocked for much longer.
No setting/backup combination has a positive full-sample day-clustered 95% interval. A few combinations are nominally positive in both non-stress splits, but by less than about $2 per spread, and they either fail on the stress dates or rely on long waits to a time cutoff. That is not sufficient evidence for live activation.
Stop-event result
| Setting | Blocked at original trigger | Short spikes suppressed within 60s | Still ineligible after 90m | P95 delay when blocked then opened |
|---|---|---|---|---|
| Factor .35 / Min 25 / Median 1 | 11 (3.4%) | 0 | 3 | 19s |
| Factor .50 / Min 10 / Median 5 | 26 (8.0%) | 12 | 12 | 50s |
| Factor .65 / Min 10 / Median 5 | 34 (10.5%) | 12 | 12 | 55s |
| Factor .80 / Min 10 / Median 5 | 40 (12.3%) | 17 | 12 | 448s |
The 325-event table shows the trade-off: stronger settings suppress more brief triggers, but also gate more ordinary stops and lengthen the delayed-exit tail. A day-clustered 10,000-sample bootstrap found no setting with a reliably positive modeled P/L interval. For the Factor .50 / Min 10 / Median 5 example, the modeled mean was +$46.24 per one-contract event, but the 95% interval ranged from −$43.49 to +$183.30. Excluding 18 May, its mean fell to −$19.61.
The named slippage events
| Event | What the evidence supports | What the gate would have done |
|---|---|---|
| October 2025 | 10 October had 15 stopped positions and finished +$1,876.84; 14 October had 65 stopped positions and finished −$33,933.58. These were Options Omega/Rob portfolio events, not native OptionsApp individual-leg lifecycles. | Useful as external stress context, but not eligible for an exact OptionsApp replay. Any claim that a setting would have “saved October” would be hypothetical. |
| 18 May 2026 | Broker execution evidence confirms a 7465 call stop filled at $50.30 at 15:02:23 ET; the surrounding one-second market was severely dislocated. | All studied gates blocked the first stop event. The weak pilot gate reopened after 16–18 seconds, but executable asks then ranged from $19.50 to $90 across the four affected legs. The vendor example never reopened within 90 minutes. |
| June–July 2026 | Population replay, not only spectacular losses, is included in the 325-event cohort. | Results are mixed. Outside 18 May, stronger settings produced negative modeled outcomes and wider delayed-stop tails. |
| 5 August 2026 | A 3.22-premium short put stopped at 12.80 during a genuine underlying move. | The weak setting did not block. The vendor example delayed eligibility by two seconds, when the displayed ask was $60—evidence that the feature can worsen timing. |
| 10 August 2026 | Local licensed chain and print coverage currently ends on 5 August. | Not replayed. It remains a pending data gap, not a backfilled claim. |
Replay can determine whether the gate would have been true under observed quotes. It cannot reconstruct the fill of an order that was never sent: queue position, venue routing, REL repricing, market impact, and the changed position state are unobserved. The P/L scenario therefore uses the next one-second NBBO ask and holds the long wing to settlement; it is a bound, not an observed fill.
What settings should we start with?
There is no evidence-backed “best” live setting. Start with two shadow arms: Factor .35 / Min 25 / Median 1 as a weak guardrail, and Factor .50 / Min 10 / Median 5 as the vendor-example comparator. Keep both from changing live exits until a future frozen holdout and live wiring test meet pre-registered safety limits.
| Actual short-leg entry premium | Starting decision | Why |
|---|---|---|
| Up to $1.50 | Keep OFF; shadow telemetry only | 103 spreads; no combination was positive in both non-stress splits |
| $1.51–$2.25 | Priority shadow tier | 305 spreads; small non-stress timer gains reversed into severe stress losses |
| $2.26–$3.50 | Shadow comparator only | 494 spreads; nominal time-cutoff result, but July improvement rounds to zero |
| Above $3.50 | Keep OFF | 590 spreads; no combination was positive in both non-stress splits |
Do not tier on target premium alone. Record actual short-leg entry premium, option stop price, distance/delta at entry, minutes to close, side, VIX/VIX1D, quote age and width, spread width, and REL parameters. A fixed 10 SPX points does not represent the same risk at 10:00 and 15:45.
How should we evaluate it safely?
- Step 1
Create a control
Duplicate one eligible short-leg template and keep the original price-only stop unchanged.
- Step 2
Run two shadow arms
Log .35/25/1 and .50/10/5 thresholds without allowing them to change production exits.
- Step 3
Verify every minute
Compare OptionsApp Trade Log reference price, reference strike, distance and threshold with the TWS condition.
- Step 4
Pre-register failure limits
Define maximum delay, never-eligible rate, stale-threshold tolerance and a hard backup exit before scoring results.
- Step 5
Require a future holdout
Do not start a live pilot until frozen future data confirms the effect outside the known May and August incidents.
- Step 6
Promote by tail controls
Require lower p99/CVaR without breaching limits for p95 delay, unresolved stops, or connection failures.
What else should we evaluate?
- Exact option trigger basis: bid, ask, midpoint, last, or broker trigger method.
- Whether the reference strike set is OTM-only and how equal-distance ties break.
- Minute-clock alignment, median warm-up, quote freshness, and missing-chain behaviour.
- Simultaneous AND versus a latched option trigger.
- Threshold update churn and stale thresholds after 1, 5, and 15-minute OptionsApp/TWS outages.
- REL Offset and REL Limit sensitivity after the gate opens.
- Delay distribution, never-eligible rate, maximum adverse excursion, full-width losses, CVaR95/99, worst day, and maximum drawdown.
- Matched controls by time, premium, side, volatility, delta, and spread width.
- A future frozen holdout or randomized smallest-size A/B. Paper trading proves wiring; only prospective live evidence tests tail liquidity.
Frequently Asked Questions
- Does the condition replace the option stop?
- No. The option stop remains one condition. The underlying distance is a second condition joined with AND.
- Does it guarantee a better fill?
- No. It controls eligibility only. REL behaviour, the order limit, liquidity and broker routing still control execution.
- Is Factor .50, Min 10, Median 5 the recommended default?
- No. It is the vendor's worked example. In the all-entry replay it blocked 26 price stops, had 13 natural gates that never reopened, and lost modestly in both non-stress evaluation splits.
- Which premium band should be tested first?
- The $1.51–$2.25 actual short-leg entry-premium band is the priority shadow cohort because it matches the known May stress mechanism. That is a test priority, not proof of superiority.
- Can the Cashflow Engine export enable it automatically?
- Not currently. Configure and verify the eligible individual short leg inside OptionsApp after import.
- Why is 10 August missing from the replay?
- The local licensed one-second SPXW chain and print shelf currently ends on 5 August 2026. We report the gap instead of extrapolating.
Terms & Definitions
- Eligibility gate
- A condition that must be true before an order may act; it does not guarantee execution.
- Reference strike
- The option strike whose observed price is closest to the stop price multiplied by Factor.
- Min. distance
- The floor applied to the calculated SPX-to-reference-strike distance.
- Median over
- The number of one-minute distance readings used for smoothing.
- REL order
- An Interactive Brokers relative order whose price follows a reference market subject to configured offset and limit rules.
- Shadow mode
- Calculating and logging decisions without allowing the new rule to change live orders.
Related pages
Mandatory pit stop: Options trading involves significant risks and is not suitable for every investor. Past results are no guarantee of future performance.