diff --git a/docs/backlog/P2/B-0545-b0498-collision-renumber-sweep-2026-05-15.md b/docs/backlog/P2/B-0545-b0498-collision-renumber-sweep-2026-05-15.md
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+---
+id: B-0545
+priority: P2
+title: B-0498 ID collision — renumber sweep (Riven cursor-terminal scaffold → new ID)
+type: substrate-correction
+status: open
+created: 2026-05-15
+filed_by: otto-cli
+depends_on: []
+composes_with:
+  - "memory/feedback_b0451_per_collision_renumber_procedure_external_references_rule_trumps_first_merged_2026_05_14.md"
+  - "B-0498-substrate-evolution-algebra-rule-promotion-after-cooling-period-2026-05-14"
+  - "B-0498-riven-cursor-terminal-background-loop-ide-native-autonomous-gate-2026-05-15"
+---
+
+# B-0545 — B-0498 ID collision renumber sweep
+
+## Observation
+
+`git ls-tree origin/main -- docs/backlog/` returns **two** files claiming the B-0498 ID:
+
+```
+100644 blob b9f58c058e371297daef7972be75ffc60bc98da0  docs/backlog/P1/B-0498-riven-cursor-terminal-background-loop-ide-native-autonomous-gate-2026-05-15.md
+100644 blob 4a70acd550adb763d219871b86fea00726e1a567  docs/backlog/P2/B-0498-substrate-evolution-algebra-rule-promotion-after-cooling-period-2026-05-14.md
+```
+
+The collision was caught by `copilot-pull-request-reviewer` on PR #3604 (tick shard 2217Z) — substrate-honest credit to the automated reviewer.
+
+## Rule for renumber
+
+Per `memory/feedback_b0451_per_collision_renumber_procedure_external_references_rule_trumps_first_merged_2026_05_14.md`:
+
+> first-merged wins; external references to the kept ID are the rule's authority; the colliding-new-row renumbers.
+
+Apply:
+
+- **P2/B-0498-substrate-evolution-algebra-* (dated 2026-05-14)** — predates by 1 day → **keeps B-0498**.
+- **P1/B-0498-riven-cursor-terminal-* (dated 2026-05-15)** — postdates → **renumbers** to next free ID.
+
+## Next free ID
+
+At time of filing (2026-05-15T22:55Z), `git ls-tree origin/main` plus `gh pr list --search "B-NNNN" --state all` shows:
+
+- B-0542 last on main
+- B-0543/B-0544 taken in flight (PR #3614, OPEN)
+- B-0545 — THIS ROW, claimed
+- **B-0546** — next free for the renumber target
+
+## Sweep scope (estimate before doing the work)
+
+External references to B-0498 that need cross-walk:
+
+1. The backlog file itself: `docs/backlog/P1/B-0498-riven-cursor-*.md` → rename to `docs/backlog/P1/B-0546-riven-cursor-*.md`
+2. PR titles referencing B-0498 in the Riven sense:
+   - #3603 (merged) — `feat(riven): Riven cursor-terminal loop scaffold [B-0498] (decomposed)` — historical record; do NOT edit merged-PR title; note in row body
+3. Tick shards referencing #3603 with `B-0498` quote:
+   - `docs/hygiene-history/ticks/2026/05/15/2217Z.md` (already merged via #3604; thread-resolution on #3604 references this row)
+   - Possibly other shards from concurrent sessions
+4. Memory files / rule files / skill files: search needed
+5. Tools/scripts referencing the Riven loop by B-0498 name: search needed
+
+## Substrate-honest scope-bound
+
+The renumber is a **substrate-correction**, NOT a feature. Implementation:
+
+- Move file: `git mv docs/backlog/P1/B-0498-riven-* docs/backlog/P1/B-0546-riven-*`
+- Update `id:` frontmatter inside the moved file
+- Update any `depends_on:` / `composes_with:` fields in OTHER backlog rows that pointed at B-0498 in the Riven sense
+- Update tick shards that QUOTE the Riven B-0498: PER `tick-shards-are-immutable` discipline, do NOT in-place-edit; instead, append a correction note in a new shard OR add a glossary entry in the renumber row
+- Update any tools/scripts: rename references via `grep -rln "B-0498-riven\|B-0498.*riven" memory/ docs/ .claude/ tools/`
+
+This row IS NOT the implementation — it's the rule-defined filed-correction surface. Implementation happens in a follow-up PR.
+
+## Why P2 priority
+
+The collision exists but doesn't actively break anything immediately:
+
+- Both files exist; no automated tooling currently fails on the duplicate ID (no enforcement)
+- The Riven scaffold (#3603) is merged and functional; renaming doesn't undo the substrate
+- The pre-existing B-0498 (algebra-rule-promotion) is referenced by various substrate; renaming IT would propagate further
+
+P2 cadence: address within the next 1-2 weeks; pair with the renumber sweep tools if available.
+
+## Composes with
+
+- The `b0451_per_collision_renumber_procedure` memory (2026-05-14) — same shape, second instance
+- The `claim-acquire-before-worktree-work.md` rule's "ID allocation discipline" section — this collision is an instance the discipline is meant to prevent
+- `refresh-before-decide.md` invariant at ID-allocation scope — both surfaces (merged + in-flight) must be checked; the Riven-cursor row at 2026-05-15 likely skipped the on-disk B-0498 P2 check