diff --git a/AGENTS.md b/AGENTS.md
index f57e6a1..23e4c42 100644
--- a/AGENTS.md
+++ b/AGENTS.md
@@ -113,9 +113,10 @@ src/client/       React app, service worker, manifest
                   useCustom.ts — the reader's own games and events (PRD F13)
                   lens.ts — who sees which rows (focus, outstanding, next-to-expire); pure
                   zoom.ts — the timeline's scale ladder; pure
+                  lanes.ts — how the timeline stacks: a lane per game, or one deadline queue; pure
 scripts/          build-feed.ts, build-static.ts, parse-fixture.ts (offline), refresh-sources.ts (fetches)
 serve.ts          static server + /api/health
-test/             599 tests
+test/             606 tests
 fixtures/<game>/  raw HTML + .expected.json per source — pinned, kept forever
 snapshots/        current page per source, rewritten by refresh — see its README
 ```
diff --git a/docs/ARCHITECTURE.md b/docs/ARCHITECTURE.md
index 4cf40b4..395cfe0 100644
--- a/docs/ARCHITECTURE.md
+++ b/docs/ARCHITECTURE.md
@@ -126,6 +126,7 @@ src/
       sort.ts           deadline order, or what you're partway through
       lens.ts           who sees which rows — focus, outstanding, next-to-expire
       zoom.ts           the timeline's scale ladder; pure
+      lanes.ts          how the timeline stacks — lanes, or one deadline queue; pure
       useAppUpdate.ts   is a newer build waiting, and taking it   (F14)
 serve.ts                static server + /api/health              ✓ built
 scripts/
diff --git a/docs/DATA-MODEL.md b/docs/DATA-MODEL.md
index bb91ff1..07e7e95 100644
--- a/docs/DATA-MODEL.md
+++ b/docs/DATA-MODEL.md
@@ -218,12 +218,15 @@ Namespaced, versioned, and small. Nothing here ever goes to the server.
 "gacha-tracker:v1:daily"        // { [id]: { days: ["2026-08-15", ...], at } }
 "gacha-tracker:v1:ignored"      // { [eventId]: { at } }  — "stop showing me this"
 "gacha-tracker:v1:prefs"        // { region, hiddenGames[], knownGames[]?, focusGame, sort, view,
-                                //   timelineDayWidth, detectDaily, showCompleted, showIgnored,
-                                //   regionConfirmed, onboarded }
+                                //   timelineDayWidth, timelineGroup, detectDaily, showCompleted,
+                                //   showIgnored, regionConfirmed, onboarded }
                                 // timelineDayWidth is px per day on the board, stored as the
                                 // measurement rather than a step number and read through
                                 // snapDayWidth — so a value from an older ladder still opens
                                 // on something renderable.
+                                // timelineGroup is "game" (a lane each) or "ending" (every game
+                                // in one deadline queue). Defaults to "game", so shipping it
+                                // moved nobody's board; see PRD F1.
                                 // knownGames is every lane the reader has been offered. Absent
                                 // means unrecorded, not "offered nothing" — see PRD F8; a lane
                                 // missing from it is new to them and arrives switched off.
diff --git a/docs/PRD.md b/docs/PRD.md
index d6bbe42..920cc2f 100644
--- a/docs/PRD.md
+++ b/docs/PRD.md
@@ -66,8 +66,8 @@ no stored key. A game may have several sources; see `docs/INGESTION.md` § Three
 ### Features
 
 **F1 — Timeline view.**
-A horizontal timeline, one lane per game, spanning a scrollable date range with "today" pinned as a
-vertical marker. Each event is a bar from `startsAt` to `endsAt`. Bars are colored by game, and
+A horizontal timeline, by default one lane per game, spanning a scrollable date range with "today"
+pinned as a vertical marker. Each event is a bar from `startsAt` to `endsAt`. Bars are colored by game, and
 completed events render at reduced opacity with a check. Clicking a bar opens a detail panel with
 title, type, exact start/end in the user's local timezone, source link, and a completion toggle.
 
@@ -81,6 +81,20 @@ calendar on screen, and nothing left saying which day, whose game, or which even
 six-week bar starts weeks off-screen, so a name that rides off with its own start date leaves a
 coloured rectangle behind.
 
+**The reader chooses how it stacks.** Lanes keep a game's events adjacent and comparable, which is
+what makes the board readable for someone playing four of them — but that reader also has one queue
+of deadlines, and lanes scatter it: what ends tonight sits three lanes below what ends next month,
+and no scroll position puts them side by side. So a pair of pills in the board's header switches
+between **By game** and **Ending soonest**, and the choice is remembered (`prefs.timelineGroup`,
+default `"game"` — the board every existing reader already has). Merged, the order is
+`endingSoonestFirst`, the same comparator behind the list's "Ending soonest" (F2), so the two views
+cannot mean different things by the same words and an unannounced end still sorts behind every dated
+one rather than claiming a place in the queue. Merged there is also no lane heading to say whose
+event a bar is, and hue alone cannot answer that once thirteen games share a stack — so each bar
+carries its game's short name, with the full name in its tooltip. A bar too narrow for a tag and a
+title both keeps the title: a chopped game name reads as a broken word, and the hue and the tooltip
+still answer it.
+
 **The reader sets the scale.** A patch cycle is six weeks and a login campaign can run for months,
 so no single density answers both "what am I in the middle of this week?" and "how do the next three
 months line up?". A pair of controls steps through a ladder of day widths, and the choice is