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+# PROCITY — Round 16 lane instructions (from Fable, integrator)
+
+Date: 2026-07-16 · **v3.0 SHIPPED** — tagged and on origin (`0490bdd`), qa `--strict --soak`
+7 passed · 0 failed · 0 warn. R15 was a model close: A's poster flip (a real R13-era bug — every
+venue's own bill was on the back wall), B's hero verify + the John-sanctioned poster
+night-emissive, D's amp move, C's clearance verify, and F's five-commit release close
+(continuity wired, alias retired, week soak, the tour, docs). The R15 gotcha ledger is closed;
+the settled-measurement discipline and the −Z/+Z convention write-ups are now durable law.
+
+Round 16 is **v3.1: THE FLIP** — the town shows its best by default. `?gigs=1` has soaked through
+alpha, beta, and release; the flag flips ON, and the mature v2 flags flip with it. Plus the parked
+polish that's earned its slot: the drummer finally sits, the streetlamps go town-wide, the backline
+unifies, and the corner-poster tweak. Tag **`v3.1`** at close.
+
+## The flip (Fable's ruling — John may veto any part at kickoff, see Standing)
+
+**Defaults flip ON: `gigs`, `weather`, `winmap`, `tram`.** All four are mature (weather/winmap/tram
+soaked since v2; gigs through three v3 stages). Each keeps an individual opt-out (`?gigs=0`,
+`?weather=0`, `?winmap=0`, `?tram=0`), and a new **`?classic=1`** forces all four off at once.
+
+**The prime law is REWRITTEN, not repealed — the covenant moves to `?classic=1`:**
+- **Classic law:** the `?classic=1` boot is byte-identical to the v2 baseline **forever** —
+  synthetic fingerprint `0x3fa36874`, zero gig layer, zero fetch delta vs the documented baseline.
+  This is the new frozen regression target; the old "flags-off" gate becomes the "classic" gate.
+- **Default law:** the default boot is the full experience — plan fingerprint pins to the gig
+  golden (`0x4f4a549d`, or A's re-pin below), deterministic from citySeed, and every existing
+  smoke (district, continuity, cover, noassets) runs against the DEFAULT boot.
+- `?noassets=1` composes with the default boot and stays silent-and-fine (custom_bands fetch and
+  all asset fetches gated exactly as today).
+
+Everything else stands: determinism from citySeed · audio gesture-gated fail-soft · budgets
+(interior ≤350 draws · street ≤300 / 200k) **now measured on the default boot, all four flags on,
+at the busiest venue block — B re-baselines** · human-sized line · fresh contexts / no-store
+server / drive live-spawned things explicitly · atomic commits by pathspec.
+
+## The ledger
+
+1. **The flip itself (F).** Shell defaults + `?classic=1` + the individual `=0` opt-outs, then the
+   harness: `flags_check.py`'s "flags-off regression" arms swap to **classic regression**
+   (`?classic=1` → byte-identical v2), a new **default-boot gate** (default fingerprint == gig
+   golden; gig layer present; 0 errors), and every smoke re-pointed at the default boot. qa.sh
+   gate names updated. This is the round's structural change — land it FIRST.
+2. **The drummer sits (E produces, D wires).** E: fetch `Sitting_Idle.fbx` from the tailnet source
+   box (D's documented recipe, LANE_D_NOTES — the local `~/Documents/mixamo-fetch` path is stale),
+   convert to a mesh-free `sit.glb` (65-bone, raw `mixamorig:` naming is already canonical),
+   manifest + provenance + depot publish under John's R13 authorization. D: the shared-rig-stack
+   wiring — a `_rotWithHips` variant (keep `Hips.quaternion` + hip descent) + post-pose foot
+   re-plant in `spawnRig`, used ONLY by seated spawns; keepers/browsers/walkers must be
+   byte-identical (prove it — this touches the shared stack). Drummer retires `SEAT_DROP` and the
+   `m.seated` sink. **Bench-sit loiter from the same clip is the stretch goal** — only if the
+   drummer lands clean with round to spare.
+3. **Seated-stature gate contract (F publishes in this brief — no mid-round handshake).** A seated
+   figure fails the no-giants floor by design. Contract: D tags seated figs
+   `fig.userData.procitySeated = true`; F's `interior_scale_check.py` + `flags_check.py` stature
+   asserts accept seated figs at **stature ∈ [0.9, 1.5] m** (still < ceiling, feet planted). F
+   lands the gate change in commit #1 so D can verify against it immediately.
+4. **Town-wide streetlamp pools (B).** Ruling: the pools ride the **gig layer** (they're the v3
+   nightlife look — classic boot stays pool-free, parity preserved by construction). Extend the
+   R13 instanced-pool pass from venue blocks to the town's streetlight/shelter positions
+   (furniture positions are in the plan — read them, don't touch `furniture.js`). Night-driven as
+   now. Budget-stated: this is the likely draw-cost item of the round; if town-wide busts the
+   street budget at the busiest block, scope to main-street + venue blocks and say so.
+5. **`stage.backline[]` unification (C, then D).** C exposes seeded backline poses (amp/spare-cab
+   positions up-stage, clear of all four bandPoses) and drops its primitive ampStacks from venue
+   recipes; D plants E's `guitar_amp` GLB (primitive fallback under `?noassets`) at `backline[]`
+   instead of its own hardcoded pose. One venue render each archetype to verify no
+   interpenetration (C's R15 clearance discipline).
+6. **Corner-poster tweak (A).** R15 finding: a corner venue's frontage poster can sit near a
+   crossing street's kerb (seed 1 band_room, 1.58 m). Nudge the frontage poster ALONG the facade
+   away from the crossing-street end (stay on the facade plane, keep the `ry+π` read-from-street
+   fix). Moves `plan.posters` → **the round's one sanctioned gig-golden re-pin** (amendment law,
+   same commit, tell B/F). Re-run the 400-seed sweep; keep the frontage-poster exemption honest
+   (assert distance-to-crossing-kerb ≥ some floor now that you control it).
+7. **No-spine osm fixture (A).** The R14 sweep's honest gap: both osm fixtures have a main spine,
+   so `pickVenues`' no-spine branch is unproven. Build the minimal single-row fixture and add it
+   to the sweep.
+
+Parked still (v3.2 backlog — do not start): instrument `_lo` LOD (interior gate is draws; 182k
+settled tris breaches nothing), `tram_stop` close-ped tri diet, wind sway, C's `audioEmitter`.
+
+## Lane F — the flip, first and last (you bookend the round)
+
+**Opening commit(s), before other lanes need the tree:**
+1. Ledger #1 — the shell flip + `?classic=1` + harness rework. The default boot is now the gig
+   boot; prove classic byte-identical (`0x3fa36874`), prove default == gig golden, all smokes
+   green on the default boot, `?noassets` silent-and-fine on the default boot.
+2. Ledger #3 — the seated-stature gate contract, same opening push.
+
+**Closing, after all lanes land:**
+3. Re-run everything: `qa.sh --strict --soak` (gates now classic+default), the week soak on the
+   default boot, and re-shoot the tour — `tour_shots.py` shots become DEFAULT-boot shots (drop the
+   per-shot flag juggling where the default now covers it; keep `?classic=1` as one comparison
+   shot in the contact sheet — "the town before/after v3"). New shots into `docs/shots/release_v3_1/`.
+4. Docs: CITY_SPEC gets the v3.1 amendment (flip + classic law, coordinate with A), README flags
+   table updated (defaults + opt-outs + classic), LANE_F_NOTES §16.
+5. Tag **`v3.1`**, push main + tag (standing authorization).
+
+## Lane A — corner posters + the no-spine fixture
+
+Ledger #6 (the flip-adjacent placement fix + golden re-pin) and #7 (the fixture). CITY_SPEC v3.1
+amendment wording with F (you own the spec; F owns the flags table). Nothing else — your sweep and
+freeze machinery is exactly right as-is.
+
+## Lane B — town-wide pools + the default re-baseline
+
+1. Ledger #4 — the pools, town-wide, gig-gated, night-driven, instanced.
+2. **Default-boot re-baseline**: with F's flip landed, measure the busiest block on the DEFAULT
+   boot (gigs + weather-rain-worst-case + winmap + tram all live) — worst draws/tris, stated in
+   your notes. This is the number the budget law now means. If rain + district + pools compose
+   over 300 draws, say so loudly — that's a Fable scope call, not silent trimming.
+3. Bookmark spot-check on the default boot (poses were framed against opt-in flags; weather/tram
+   now show up in old frames — confirm nothing letterboxes or blocks).
+
+## Lane C — the backline handoff
+
+Ledger #5, C's half: `stage.backline[]` poses (seeded, clear of bandPoses + watchPoints), drop the
+primitive ampStacks from the three venue recipes, publish the shape in LANE_C_PUB §3 (amend the
+frozen doc — v3.1 marker, same discipline as A's spec amendments). Verify with D once wired.
+
+## Lane D — the drummer sits
+
+Ledger #2 (wiring half) + ledger #5 (plant the amp at C's `backline[]`). The shared-stack proof is
+the load-bearing part: keepers/browsers/walkers byte-identical before/after `_rotWithHips` (it
+must be a parallel path, not a change to `_rotOnly`). Tag seated figs per ledger #3. Bench-sit is
+stretch — drummer first, prove it, then decide.
+
+## Lane E — the sit clip + provenance
+
+Ledger #2 (asset half): fetch → convert → `sit.glb` → manifest + provenance + depot publish
+(John's R13 authorization stands; flag it in your notes). Update the frozen provenance table with
+a v3.1 amendment marker. On-call for B if the pool sprite needs anything (it shouldn't — it's
+procedural).
+
+## Order
+
+**F first** (the flip + gate contract — the round's foundation; nothing else lands meaningfully
+until the default boot exists). Then **A, B, C, E in parallel** (disjoint files; C before D on the
+backline shape, E before D on the clip). **D** once C's backline + E's clip + F's gate are in.
+**F last** (re-baseline acceptance, tour, docs, tag `v3.1`). Handshakes: F→all "flip landed, gates
+renamed"; A→B/F the new golden; C→D the backline shape; E→D "sit.glb on depot"; B→F the default
+worst-case numbers.
+
+## Standing
+
+- **John — one decision, veto-by-kickoff:** the flip scope. Fable flips **gigs + weather + winmap
+  + tram** ON by default (`?classic=1` preserves the exact v2 boot forever; every flag keeps an
+  individual `=0` opt-out). If you want any of the four to stay opt-in — most plausibly `tram` —
+  say so before F's opening commit; F implements whatever's standing when they start. FYI: the
+  gig golden re-pins once (A's corner-poster fix), and E publishes `sit.glb` to the depot under
+  your R13 authorization.
+- **v3.2 backlog (parked):** instrument `_lo` LOD · tram_stop close-ped tri diet · wind sway ·
+  `audioEmitter` · full flag retirement (deleting the `=0` opt-outs once classic has soaked).