SCENARIO PROBABILITIES Updated: Jul 22, 2026
The tree turns on a signal that flipped rather than settling. Tuesday's six-vessel diversion, headlined by the VLCC Xin Long Yang, read as the start of a one-way exodus from the Yanbu-Bab el-Mandeb corridor, the same pattern that preceded Hormuz's own war-risk closure. By Wednesday afternoon the Xin Long Yang had reversed again, sailing back toward the strait on its original routing, while three other flagged vessels sat idling or diverting to Suez. That is not a resolving signal, it is a market still arguing with itself, which is why Path 1 (the embargo stays a pricing event, not a physical one) and Path 2 (a confirmed strike breaks the argument) split the largest shares of probability almost evenly. Riyadh's Jul 22 threat of force against the blockade is new and structurally different from anything in this corridor's history, since Saudi Arabia has spent five months as the one Gulf capital that stayed out of direct kinetic exchange; that alone earns its own path. The diplomatic path stays a genuine but a minority case: deal-collapse has sat at 85-90% for weeks with no single day moving it, and Iran's Interior Minister shuttling through Islamabad has not yet produced anything Riyadh or Sana'a have acted on. Every path inherits the same hard ceiling this desk mapped in One Route Left: deliverable spare capacity covers only 15-25% of the ~2.5M bbl/day at stake if Yanbu's Asia leg genuinely fails, so the range between paths is really a range in how much of that gap the market prices before a resolution, not whether the gap itself closes.
The Reversal Repeats 30%
No vessel struck, diversions and returns keep alternating, Yanbu-to-Asia runs reduced but not dead $90-96
The Strike That Confirms It 25%
First vessel hit or boarded specifically at Bab el-Mandeb, tonnage refusal cascades $98-112
Riyadh Pulls the Trigger 20%
Saudi Arabia acts on its force threat, direct Saudi-Houthi exchange opens a new sub-theater $93-105
Momeni's Channel Pays Off 15%
Pakistan-mediated track lands, Houthis stand down the blockade inside a wider package $82-89
The Black Sea Eclipses the Gulf 10%
Kazakhstan's CPC shock deepens independently and crosses the alert line before Bab el-Mandeb resolves either way $96-115+

The VLCC Xin Long Yang has now made the same decision twice, in opposite directions, a day apart. Tuesday it turned away from a Saudi-bound run through Bab el-Mandeb, one of at least six vessels that reversed course rather than test the Houthi embargo declared against Saudi Arabia the day before. By Wednesday afternoon it had reversed again, sailing back toward the strait on its original routing. No missile has been fired at it. No underwriter has cancelled its cover. The ship's own master, or whoever is directing that vessel's charter, changed their mind twice about a threat that has not itself changed at all. That is the most honest data point available on the Yanbu bypass right now: nobody transiting it, insuring it, or threatening it has settled on what it actually is.

This morning's TankerBrief brief read Tuesday's diversions as the hard evidence this desk had been waiting for since the embargo was declared. The Wednesday reversal complicates that read without erasing it. Three other flagged vessels are still behaving as if the threat is real: the LPG carrier Gas King diverted to Suez after loading at Yanbu, the supertanker New Explorer is idling near the port with its AIS status reading "not under command," and the Aframax Lahore halted mid-voyage after loading. One ship going back does not undo three others staying away. It means the market has not converged on a single answer, and a market mid-argument is exactly the setup a scenario tree exists to map.

MetricJul 20 (declaration)Jul 22 afternoonChange
Bab el-Mandeb war-risk premium~0.3% of vessel value~0.75% of vessel value+150%, no incident yet
Confirmed vessel diversions06 (1 since reversed back)Mixed, not one-directional
Saudi crude loadings (Kpler, 2-week trend)9.5M bbl/day6.1M bbl/day-36%
Brent crude~$88$94.30-95.47Sharpest single-cycle move of the crisis
Saudi public posture on the blockadeNot yet addressed"Disinformation" (Jul 21) to threat of force (Jul 22)Hardened twice in 48 hours
Kazakhstan CPC terminal (separate theater)Partial disruptionFully suspended, ~1.6M bbl/day offlineNew compounding shock

The 6.1M bbl/day loadings figure needs a caveat this desk has carried since it first surfaced: it is total Saudi crude loadings, west-coast plus Asia-bound combined, not the Yanbu pipeline specifically, and the two-week decline predates Monday's embargo declaration, tracking instead with the broader threat climate since the Jul 14 Abha strike. Treat it as directional context for the corridor under strain, not a precise measurement of what the embargo itself has done.