Warning Tier

ELEVATED — upgraded from WATCH. Named exercise criterion met: 5 Sep dual-designation "Joint Combat Readiness Patrol" + "Air-Sea Joint Drill", 17/20 sorties crossing median. Moderating: immediate de-escalation 7 Sep (2 sorties); Xi–Trump White House Sep 24 = 17 days; Polymarket before-2027 ~4% remains below ELEVATED probability band (8–15%). Cadence per the tier ladder: daily — this weekly schedule cannot meet that cadence; flag for escalation if activity persists at named-exercise level.

PLA Activity — Sep 1–7

5 Sep — ROC MND detected 20 sorties of PLA aircraft (J-11, Su-30, H-6, Y-8 EW, KJ-500), 6 PLAN vessels, 5 official ships. 17 of 20 sorties crossed the median line, entering Taiwan's northern and southwestern ADIZ. The event carried two simultaneous PRC designations: Joint Combat Readiness Patrol and Air-Sea Joint Drill — the first dual-designation event of 2026.

7 Sep — 2 sorties / 13 PLAN vessels / 4 official ships; both sorties crossed median. Rapid de-escalation from the 5 Sep spike; pattern consistent with previous post-event pullbacks.

H1 2026 context (SCMP / GlobalMilitary.net): 1,334 PLA aircraft detected Jan–Jun 2026 — a 52% drop year-on-year and the lowest six-month total since 2022. Jan–9 Aug: 1,200 aircraft, versus 2,501 over the same window in 2025. Air pressure halved; warship presence unchanged.

Significance of the 5 Sep Event

The dual designation distinguishes 5 Sep from the unnamed all-4-quadrant events of August. Previous JCRP events (Jul 30, 2026) drove the tier to WATCH; a concurrent Air-Sea Joint Drill label indicates coordination across a broader operational framework. The northwestern-quadrant inclusion in the Jul 30 JCRP versus the southwestern-quadrant emphasis on 5 Sep suggests a rotation in rehearsal geography. The Su-30 (versus J-16 in prior events) adds a Russia-supplied airframe to the mix for the first time this cycle.

Named exercise criterion met → ELEVATED. De-escalation counter-signal present but does not negate the designation. Review tier after Sep 24 summit outcome.

CCG East of Taiwan — Rotation Confirmed, Patrol Institutionalised

The Daishan-led formation (operating since June) has been replaced by a Xiushan (2305)-led group. The handover was planned, publicly announced, and framed by Beijing as "routine." Formation positions remain approximately unchanged: one vessel ~280 km east of Lanyu (Orchid Island), the second ~80 km to its northeast. Taiwan CGA patrol vessel Taipei continues to shadow both. No inspection-zone declaration; no shipping NOTAM.

Strategic assessment: Beijing presented the rotation with institutional language — "established schedule," "routine law enforcement." A rotation on a calendar, not a response to a trigger, carries the signature of a permanent patrol. This is now a standing CCG presence east of Taiwan, not a temporary deployment.

ROC MND 2026 Annual Assessment

Taiwan's Ministry of National Defense 2026 report (Sep 2, Taipei Times) flags PLA joint island-landing capability development as a priority: improving amphibious logistics, reducing response timelines, completing force transformation for integrated joint operations by 2027. The report does not assert an imminent threat, but names landing-operation rehearsal as the primary capability driver behind current exercises.

Diplomatic and Arms

Xi–Trump White House summit: Sep 24 — confirmed, 17 days out. Beijing continues to list Taiwan as the top agenda item. Bipartisan Senate bloc (SFRC) and House Select Committee (Krishnamoorthi) have issued letters to Trump urging advancement of the $14B arms package before the summit. No White House response; package status remains "in abeyance."

PAC-3 MSE deliveries: underway. NASAMS FMS: approved, completion 2031. HIMARS: Q4 2026 delivery on schedule. NT$780B special defense budget: passed May 8. Drone Act NT$240B (MoEA authority): passed Aug 27–28; Executive Yuan support announced Aug 30; implementing regulations pending.

Polymarket

Invasion before Jan 1, 2027: ~4% ($40.4M traded) · Military clash before Dec 31, 2026: ~7% · Before Jun 30, 2027: ~9.5% · Before Dec 31, 2027: ~11.5%

Probability Assessment

Ranges unchanged from the Jul 20 editorial endorsement. The Sep 5 named drill is a qualitative escalation signal; it does not shift the quantitative probability estimate without sustained follow-through.

1 month: 2–4%  |  6 months: 5–7%  |  1 year: 10–13%  |  5 years: 18–24%

Pre-summit incentive structurally suppresses near-term action. The Sep 24 Xi–Trump meeting is the primary moderating variable; summit outcome (concession on $14B arms / Taiwan policy signal / joint communiqué language) will determine whether the tier reverts to WATCH or sustains ELEVATED into Q4 2026.

Next Structural Inflections

Xi–Trump White House Sep 24 · $14B arms sale resumption (contingent on Sep 24) · HIMARS delivery Q4 2026 · PORCUPINE Act House floor vote (no date) · Drone Act MoEA implementing regulations · 2027 Party Congress