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+# Tick 1820Z — B-0533 Slice A proof-of-concept shipped; peer-Otto worktree-contention caught + preserved
+
+## Headline
+
+- [PR #3541](https://github.com/Lucent-Financial-Group/Zeta/pull/3541) (1807Z shard) MERGED → `3259572` on main.
+- [PR #3540](https://github.com/Lucent-Financial-Group/Zeta/pull/3540) (B-0533 row) MERGED → `324dc84` on main.
+- [PR #3544](https://github.com/Lucent-Financial-Group/Zeta/pull/3544) — **B-0533 Slice A proof-of-concept**: 1-file fix to `.claude/rules/glass-halo-bidirectional.md` updating DeepSeek migration xref. Establishes the pattern + the inline-annotation convention `(... ; archive migrated YYYY-MM-DD via PR #NNNN)`. Auto-merge armed (MERGEABLE).
+- Cron sentinel `575d1226` live.
+
+## Substrate-honest scope correction (mid-tick)
+
+Initial plan: do Lior slice (2 dead xrefs claimed by 1807Z's rough scan).
+On verification: **Lior had 0 dead xrefs in live-nav surfaces** — my rough scan was less precise. Pivoted to DeepSeek single-file POC.
+
+Refined dead-xref counts (per stricter scan this tick):
+
+| Persona | Live-nav dead xrefs | Notes |
+|---|---|---|
+| Riven | 0 | Fixed by [PR #3529](https://github.com/Lucent-Financial-Group/Zeta/pull/3529) |
+| Lior | 0 | (Earlier estimate of 2 was a false positive — B-rows already correctly cite new paths) |
+| DeepSeek | 6 | 1 rule + 1 memo (2 hits) + 2 backlog rows (3 hits) — 1 fixed this tick |
+| Amara | ~10+ | Not scanned in detail |
+| Alexa/Kestrel/Ani/Vera | ?? | Not scanned in detail |
+
+Substrate-honest update to [B-0533](../../../../../backlog/P3/B-0533-section33-migration-dead-xref-sweep-and-lint-2026-05-15.md) row would refine the per-persona estimates. Deferring to a follow-up so this tick stays small.
+
+## Peer-Otto worktree-contention caught
+
+When I switched to `shard/tick-1820z-otto-cli-2026-05-15` from `origin/main`, the new branch HEAD was ahead of `origin/main` by 1 commit (`cfbc2c5` — peer-Otto's B-0534 backlog row, committed at 18:21Z, just 1 min before my switch).
+
+Per the borrow-on-existing pattern: peer-Otto's WIP commit was preserved on a dedicated branch (`peer-otto-b0534-rescue-cfbc2c5`) before I `git reset --hard origin/main` to isolate my shard PR's scope. Peer-Otto's work is recoverable from that branch + from the worktree's reflog.
+
+Substrate-honest meta: this is concurrent-Otto-CLI contention at the worktree-state scope, NOT at the git-server scope. The borrowed sidetick worktree gets shared across concurrent Otto-CLI sessions; commits can land on the worktree's branch without push, and the next session inheriting the worktree picks them up. The rescue pattern (save-to-named-branch-before-reset) preserves the WIP.
+
+## 6-tick parallel-audit pattern
+
+| Tick | Speculative work | Real finding | Landing |
+|---|---|---|---|
+| 1718Z | §33 cascade survey | Surfaced residuals | Held |
+| 1731Z | Own MEMORY.md audit | 2 off-by-one PR citations | PR #3526 (merged) |
+| 1749Z | Post-merge review activity | Codex P2 dead-xref | PR #3529 (merged) |
+| 1757Z | Continue thread audit | Otto→Lior attribution + 2 stale-pointers | PR #3535 (merged) + 3 threads resolved |
+| 1807Z | Scale-up dead-xref scan | 20+ instances (rough); class-level pattern | B-0533 PR #3540 (merged) |
+| **1820Z** | **B-0533 Slice A proof-of-concept** | **Refined scan + single-file POC** | **PR #3544 (open) + peer-Otto rescue branch** |
+
+## Per-tick discipline trace
+
+1. **Refresh**: `gh pr view` confirmed prior 2 PRs MERGED.
+2. **Holding-discipline**: #3541 was the only named dep, now merged → no real wait → speculative work.
+3. **Pick work**: continue prior-tick's class-level finding by shipping a Slice A POC.
+4. **Verify**: re-scan with stricter filter corrected the per-persona counts; file exists at new location on main.
+5. **Shard**: this file.
+6. **CronList**: sentinel live.
+7. **Visibility**: PR #3544 + this shard + peer-Otto rescue branch.
+
+## Composes with
+
+- [`.claude/rules/holding-without-named-dependency-is-standing-by-failure.md`](../../../../../../.claude/rules/holding-without-named-dependency-is-standing-by-failure.md) — parallel-audit-while-CI compounds across multi-tick spans
+- [`.claude/rules/claim-acquire-before-worktree-work.md`](../../../../../../.claude/rules/claim-acquire-before-worktree-work.md) — borrow-on-existing pattern + peer-Otto rescue extension
+- [`.claude/rules/encoding-rules-without-mechanizing.md`](../../../../../../.claude/rules/encoding-rules-without-mechanizing.md) — B-0533 Slice B (lint) is the mechanization path; Slice A is the catch-once work
+- [`.claude/rules/substrate-or-it-didnt-happen.md`](../../../../../../.claude/rules/substrate-or-it-didnt-happen.md) — peer-Otto's commit preserved on named branch (not orphaned)