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+# PLAN-BACKUP3-X10-CANONICAL-MAP — Update ole-blu backup3 to the X10 canonical structure
+
+Status: DRAFT for operator review (no execution yet). 2026-08-20.
+Canonical copy: `~/dev/_shared/docs/plans/` (Tangled-synced; repo is PUBLIC — paths only, no secrets).
+Related: `docs/BACKUP3-PLAN.md`, studio `~/msd512-audit/PLAN-3B-X10-REORG.md` +
+`PLAN-3B-EXECUTION.md` (STEP 5 = this task), `backup-move-scripts` skill.
+Owner: Patrick Singletary.
+
+## 0. Live status (Mac Studio, 2026-08-20 ~07:15 EDT)
+
+- Crucial 2TB -> X10 backup/mirror: COMPLETE (112,656 files, 840 GiB, 0 errors) at
+  `/Volumes/Crucial X10/_photos-library-mirror/`.
+- X10 full inventory + dedup analysis: COMPLETE (230,326 files, all sha256; 671 GiB recoverable).
+- X10 reorg STEP 2 (move+dedup): RUNNING in tmux `x10-step2` (caffeinate) since ~06:21.
+  ~50.7k / 122k rows done (~41%) at 07:11; ledger `~/msd512-audit/run-x10/move-ledger.tsv`.
+  Move plan: 111,520 MOVE rows (1,999.5 GiB) + 10,526 DEDUP rows (555.2 GiB), 0 conflicts.
+- Remaining gates: GATE-2 (move ledger review) -> STEP 3 (empty legacy dir cleanup) ->
+  GATE-3 -> STEP 4 (verify + freeze) -> GATE-4. Structure is NOT frozen yet.
+- ole-blu backup3: launchd LIVE (60s interval, --apply), correctly no-op'ing ("X10 not
+  mounted", last run 07:09). Safe until the X10 physically attaches to the Air.
+- mac-studio backup3: launchd UNLOADED (reorg R7), NO live `~/.config/backup3/` — inert.
+  Its future update is PLAN-3B STEP 5; this plan is its template (shared config).
+
+## 1. Goal
+
+Update ole-blu's backup3 (script + shared config) to write into the X10's post-reorg
+canonical structure, keeping per-machine subdirs so both machines back up collision-free.
+Design the mapping in SHARED config so the Mac Studio's later update reuses it as-is.
+OneDrive targets unchanged (active/small tier stays `OneDrive/<cat>/<machine>`).
+
+## 2. Canonical X10 structure (locked by reorg plan)
+
+```
+Media/{Movies,TV,Twitch,Music-Videos,Clips,Rips,Other-Video}/
+Music/ Pictures/ Documents/ Desktop/ Downloads/ QBT/{torrents,incomplete}/
+z-New folder/ Archive/ photos-restore.photoslibrary/ _ledger/ _CONFLICTS/
+```
+
+Reorg mapping that touches backup3 history: `archive/` -> `Archive/` (relative paths
+preserved, so historical per-machine dirs land at `Archive/<cat>/<machine>`),
+`downloads/` -> `Downloads/` (legacy `downloads/ole blu/` -> `Downloads/ole blu/`).
+
+## 3. Mapping: current -> canonical (per-machine subdir `<m>` appended)
+
+| Category | Current X10 target | New X10 target |
+|---|---|---|
+| Music (~/Music) | archive/Music/<m> | X10/Music/<m> (split w/ OneDrive) |
+| Pictures | archive/Pictures/<m> | X10/Pictures/<m> (split) |
+| Documents | archive/Documents/<m> | X10/Documents/<m> (split) |
+| Desktop | archive/Desktop/<m> | X10/Desktop/<m> (split) |
+| Movies (~/Movies) | archive/Movies/<m> (always) | X10/Media/Movies/<m> (always) [DP-4] |
+| Downloads/stacher | archive/stacher/<m> | X10/Media/Music-Videos/<m> (stacher = music videos, per reorg) |
+| Downloads/Media | archive/media/<m> | X10/Media/Other-Video/<m> [DP-2] |
+| Downloads/*installer | archive/installers/<m> | X10/Archive/installers/<m> [DP-3] |
+| Downloads/Music | OneDrive/Music/<m> | unchanged |
+| Downloads/*.pdf | OneDrive/Documents/<m> | unchanged |
+| Downloads/other | archive/downloads/<m> | X10/Downloads/<m> (split) |
+| Ledger mirror | archive/_ledger/ledger-<m>.csv | X10/_ledger/ledger-<m>.csv |
+| Run-log mirror | archive/_ledger/run-<m>-*.log | X10/_ledger/ |
+| Cleanup trash | X10/.backup3-trash/<date>/ | unchanged (root hidden dir) |
+
+## 4. Code changes (`~/dev/_shared/bin/backup3.zsh`)
+
+1. `run_categories` (2 call sites): x10 target `"$xd/$cat/$MACHINE"` -> `"$xd/$MACHINE"`.
+   x10_base semantic changes from "root" to "exact canonical parent"; OneDrive side
+   (`"$od/$cat/$MACHINE"`) unchanged.
+2. `route_downloads`: `xd="$ARCHIVE_ROOT"` -> `xd="$X10_ROOT"`; rewrite the five X10
+   path strings per Section 3 (stacher, Media, installers, downloads, ledger-adjacent).
+3. Ledger + run-log mirror block: `"$ARCHIVE_ROOT/_ledger"` -> `"$X10_ROOT/_ledger"`.
+4. `cleanup_pass` prune list: drop `archive`, add `_ledger`, `_CONFLICTS`,
+   `.backup3-trash`, `photos-restore.photoslibrary` (opaque bundle, never scanned —
+   matches reorg "LEAVE 108,278").
+5. NEW structure assertion (canonical_ok): after `x10_mounted`, require
+   `$X10_ROOT/_ledger` AND at least one canonical top-level (Downloads|Media|Pictures|
+   Documents|Desktop|Music); else log "X10 present but not canonical — no-op" and exit 0.
+   [DP-5] Backstop for attaching the drive mid-reorg or pre-freeze.
+6. `status()`: print canonical-marker state.
+
+Unchanged: rsync opts, size threshold, ledger schema, launchd plist, OneDrive routing,
+UUID mount check.
+
+## 5. Config changes (shared so the Studio inherits)
+
+- `~/.config/backup3/backup3.conf` (+ repo `config/backup3/backup3.conf`): add
+  `CANON_ROOT="$X10_ROOT"`; update comments. `ARCHIVE_ROOT` kept for the legacy/back-compat
+  path until the Studio migration lands.
+- `~/.config/backup3/machines/ole-blu.conf` (+ `mac-studio.conf` + repo stub): CATEGORIES
+  x10_base -> `$CANON_ROOT/<top-level>`; `Movies -> $CANON_ROOT/Media/Movies|yes`.
+  Update the schema comment (x10_base is now the exact parent).
+
+## 6. Decision points (a/b/c)
+
+- DP-1 Machine dir naming: (a) keep `ole-blu`/`mac-studio` (hyphen, current MACHINE_ID);
+  legacy `ole blu` dirs stay as history [recommended]; (b) also one-time rename legacy
+  `Downloads/ole blu` -> `Downloads/ole-blu` post-reorg + _ledger note; (c) adopt whatever
+  the reorg left and change MACHINE_ID.
+- DP-2 Downloads/Media dest: (a) X10/Media/Other-Video/<m> [recommended — reorg's
+  "undetermined video" bucket]; (b) X10/Media/Clips/<m>; (c) X10/Media/Movies/<m>.
+- DP-3 installers dest: (a) X10/Archive/installers/<m> [recommended]; (b) X10/Downloads/
+  installers/<m>; (c) X10/Archive/_misc/installers/<m>.
+- DP-4 ~/Movies routing (Air: screen recordings + iMovie Library): (a) all ->
+  X10/Media/Movies/<m> [recommended, simple]; (b) iMovie Library + screen recordings ->
+  X10/Media/Other-Video/<m>, rest -> Movies; (c) split by extension into Clips/Other-Video.
+- DP-5 Structure assertion: (a) require _ledger + one canonical top-level [recommended];
+  (b) require _ledger only; (c) no assertion (trust UUID check).
+- DP-6 Activation: (a) implement now, activate after reorg GATE-4 freeze [recommended];
+  (b) implement + activate immediately (assertion is the backstop); (c) hold until the
+  Studio script is updated too, do both in one pass.
+
+## 7. Phases (gated, same posture as the reorg)
+
+- P1 Implement: edits to backup3.zsh + confs in `_shared`; commit by filename; plain push
+  (RESUME.md flags remote force-diverged — NEVER force-push; report if rejected).
+- P2 Verify on Air: `zsh -n`; `--status`; sandbox routing harness (one file per routing
+  rule -> assert WOULD-MOVE targets are canonical, zero dirs created in dry-run,
+  assertion no-ops on a fake non-canonical X10); `plutil -lint` plist.
+- P3 Activate: copy new confs to `~/.config/backup3/` on Air; launchd untouched; first
+  supervised `--apply` the first time the X10 attaches after GATE-4.
+- P4 Verify live: ledger rows land at canonical paths; `X10/_ledger/ledger-ole-blu.csv`
+  mirrored; spot-check restores.
+- P5 Studio model (later, PLAN-3B STEP 5): same shared confs + this mapping; studio
+  installs live config, re-enables launchd (`launchctl load .../com.psingletary.backup3.plist`).
+
+## 8. Risks
+
+- Drive attached to Air mid-reorg: assertion no-ops (DP-5) + user guidance (don't attach
+  until GATE-4).
+- Legacy `ole blu` vs `ole-blu` sibling dirs (DP-1).
+- Historical restore paths change (archive/X -> Archive/X): covered by ledger + _ledger
+  provenance (reorg writes `_ledger/provenance.csv`).
+- Cross-machine dedup stays deferred (reorg GATE-0 deferred ~124 GB of cross-category
+  byte-identical dups; ExFAT has no hardlinks) — per-machine dirs intentionally duplicate.
+- `_shared` remote force-diverged: plain push only; if rejected, surface to operator.
+
+## 9. Verification checklist (after P2/P3)
+
+1. Dry-run routes each rule to the canonical target (grep WOULD-MOVE lines).
+2. No double-nested destinations (`grep -E '<top>/<name>/$'` finds nothing).
+3. Dry-run created NO directories anywhere (incl. absolute /Volumes targets).
+4. Assertion fires (exit 0, logged) against a legacy-layout fake mount.
+5. `zsh -n` on script + all confs; `plutil -lint` on plist.
+6. Live apply: ledger lines at canonical dests; `_ledger/ledger-ole-blu.csv` updated.