@@ -180,8 +180,9 @@ from a sidecar. A future `isamples_202601_oc_sidecar.parquet` (keyed on
 URL convention: each file is available at
 `https://data.isamples.org/<filename>` (versioned, 1-yr immutable cache)
 and, where applicable, at `https://data.isamples.org/current/<alias>`
-(302 redirect, 5-min cache). Examples below use the versioned URL; swap
-for the alias when you want "latest."
+(302 redirect, 5-min cache). Examples below use the versioned URL. The
+alias is a stable address, not a promise of the newest release — see §5
+for what it currently points at.
 
 ### 4.1 Zenodo export (source of truth)
 
@@ -407,9 +408,11 @@ Cloudflare Worker fronting an R2 bucket. The Worker provides:
   — 1-year immutable cache. Safe to pin in papers, Zenodo manifests,
   reproducibility notebooks.
 - **Alias URLs** `https://data.isamples.org/current/<alias>` — 302
-  redirect with 5-min cache; always resolves to the latest snapshot.
-  Use for "always fresh" consumers. Currently
-  `current/wide.parquet → isamples_202604_wide.parquet`.
+  redirect with 5-min cache to a dated file. Currently
+  `current/wide.parquet → isamples_202604_wide.parquet`, the April 2026
+  wide file the tutorials were written against. It was deliberately left
+  there when the Explorer moved to the `isamples_202609_*` release
+  (September 2026), so it is not the newest snapshot.
 
 **Never reference the raw
 `pub-a18234d962364c22a50c787b7ca09fa5.r2.dev/...` URL.** It bypasses
 
@@ -49,8 +49,13 @@ Two places depending on what you need:
   Cloudflare R2. HTTP range requests supported; DuckDB and DuckDB-WASM
   work directly against URLs. Two layers:
   - `/<versioned-file>.parquet` — 1-year immutable cache. Pin in papers.
-  - `/current/<alias>.parquet` — 302 redirect to the latest snapshot.
-    Use for "always fresh." Currently aliases:
+  - `/current/<alias>.parquet` — 302 redirect to a dated file, so
+    tutorials and notebooks have one stable address. It is **not** the
+    newest release: it is pinned to the April 2026 wide file the
+    tutorials were written against, while the Explorer reads the
+    `isamples_202609_*` files (see the
+    [release manifest](https://isamples.org/isamples_202609_release_manifest.json)).
+    Currently aliases:
     - `/current/wide.parquet` → `isamples_202604_wide.parquet`
 - **[iSamples Zenodo community](https://zenodo.org/communities/isamples)**
   — long-term archival with DOIs. The raw aggregated export is
 
@@ -450,6 +450,34 @@ format:
         position: relative;
         z-index: 1100;
     }
+    /* The rule above has a side effect, found 2026-10-07 by clicking every
+       toolbar button on the live site: the wrapper now sits above its
+       later siblings even while the picker is COLLAPSED, and its box
+       extends over the two buttons below it (the hidden 2D/Columbus
+       buttons still occupy that space). So the imagery picker and the
+       "?" help button received no clicks at all. Let clicks fall through
+       the wrapper and its hidden buttons; the visible ones still take
+       them, so #324 stays fixed. */
+    .cesium-sceneModePicker-wrapper { pointer-events: none; }
+    .cesium-sceneModePicker-wrapper > button { pointer-events: auto; }
+    .cesium-sceneModePicker-wrapper > button.cesium-sceneModePicker-hidden { pointer-events: none; }
+    /* Navigation help ("?") panel. Cesium anchors it to the button's RIGHT
+       edge and opens leftwards, which suits its default top-right toolbar.
+       Our toolbar is top-left, so the panel opened 184px off the left edge
+       of the globe and only a clipped stub was visible. Open it to the
+       right of the toolbar instead, lifted so it fits inside the
+       450px-high globe. */
+    .cesium-navigation-help {
+        left: 40px !important;
+        right: auto !important;
+        top: -150px !important;
+        transform-origin: 0 150px !important;
+        z-index: 1100;
+        /* Cesium fixes the panel at 250px. On a phone-width globe that
+           plus the 40px offset would run off the right edge, so let it
+           shrink to what the viewport can hold. */
+        max-width: calc(100vw - 96px);
+    }
     .search-bar { display: flex; gap: 6px; }
     .search-bar input {
         flex: 1; padding: 8px 12px; border: 1px solid #ccc; border-radius: 4px;
@@ -2484,6 +2512,9 @@ viewer = {
         timeline: false,
         animation: false,
         baseLayerPicker: true,
+        // Cesium auto-opens the navigation help on a visitor's first load.
+        // Keep the first view of the globe clear; "?" still opens it.
+        navigationInstructionsInitiallyVisible: false,
         fullscreenElement: "cesiumContainer",
         terrain: Cesium.Terrain.fromWorldTerrain()
     });
 
@@ -79,11 +79,13 @@ The two main files carrying the sample records themselves:
 | [`isamples_202601_wide_h3.parquet`](https://data.isamples.org/isamples_202601_wide_h3.parquet) | 307 MB | Wide + H3 BIGINT indices (`h3_res4`, `h3_res6`, `h3_res8`) | 20.7 M | Geospatial queries with H3 clustering at arbitrary zoom |
 | [`isamples_202512_narrow.parquet`](https://data.isamples.org/isamples_202512_narrow.parquet) | 860 MB | Narrow (graph: nodes + explicit `_edge_` rows, s/p/o/n fields) | 101,387,180 | Graph traversals, relationship-centric analysis, PQG work |
 
-∗ `/current/wide.parquet` is a stable alias that HTTP 302-redirects to the
-latest dated file (currently
+∗ `/current/wide.parquet` is a stable alias that HTTP 302-redirects to a
+dated file (currently
 [`isamples_202604_wide.parquet`](https://data.isamples.org/isamples_202604_wide.parquet),
-enriched with ~47 K OpenContext thumbnails). The dated filename is
-immutable; the alias rotates atomically when we rebuild. Use the alias for
+enriched with ~47 K OpenContext thumbnails). That is the April 2026 file
+these tutorials were written against, not the newest release: the
+Interactive Explorer reads the September 2026 `isamples_202609_*` files.
+The dated filename is immutable. Use the alias for
 interactive work, the dated URL when you want a pinned, reproducible
 reference. The original
 [`isamples_202601_wide.parquet`](https://data.isamples.org/isamples_202601_wide.parquet)
 
@@ -333,8 +333,11 @@ Worker in front of the R2 bucket). Two layers:
 
 - **Versioned** `/isamples_YYYYMM_<file>.parquet` — 1-yr immutable cache,
   safe to pin in papers, spec examples, or reproducibility notebooks.
-- **Alias** `/current/<alias>` — 302 redirect with 5-minute cache; tracks
-  whatever the latest snapshot is. Use for "always fresh" consumers.
+- **Alias** `/current/<alias>` — 302 redirect with 5-minute cache to a
+  dated file. As of October 2026 `/current/wide.parquet` is pinned to
+  `isamples_202604_wide.parquet` (the file the tutorials use); it does
+  **not** follow the Explorer's newer `isamples_202609_*` release. Pin a
+  versioned URL when the exact snapshot matters.
 
 Never reference the raw `pub-a18234d962364c22a50c787b7ca09fa5.r2.dev/...`
 URL — it bypasses the Worker and defeats the alias layer.
 
@@ -43,7 +43,7 @@ All data is hosted on [`data.isamples.org`](https://data.isamples.org) with HTTP
 
 | File | Size | Description |
 |------|------|-------------|
-| [Wide format](https://data.isamples.org/current/wide.parquet) | 292 MB | One row per entity, all sources — primary file for tutorials. Stable alias redirects to the current dated build (`isamples_YYYYMM_wide.parquet`). |
+| [Wide format](https://data.isamples.org/current/wide.parquet) | 292 MB | One row per entity, all sources — primary file for tutorials. Stable alias; currently redirects to the April 2026 build (`isamples_202604_wide.parquet`), not the Explorer's newer 202609 release. |
 | [Wide + H3](https://data.isamples.org/isamples_202601_wide_h3.parquet) | 292 MB | Wide format with H3 spatial indices for globe visualizations |
 | [Facet summaries](https://data.isamples.org/isamples_202601_facet_summaries.parquet) | 2 KB | Pre-computed filter counts — loads instantly |
 | [H3 clusters (res4)](https://data.isamples.org/isamples_202601_h3_summary_res4.parquet) | 0.6 MB | Zoomed-out globe view |