diff --git a/docs/database/challenges.md b/docs/database/challenges.md
index 9b4b90b..8164b55 100644
--- a/docs/database/challenges.md
+++ b/docs/database/challenges.md
@@ -3,7 +3,7 @@ type: database
 title: Challenge Tables
 description: category, challenge, challenge_file, and solve tables — how CTF challenges and scoring are stored.
 tags: [database, challenge, category, solve]
-timestamp: 2026-07-21T14:18:00Z
+timestamp: 2026-07-22T14:50:25Z
 ---
 
 # Tables
@@ -18,8 +18,8 @@ timestamp: 2026-07-21T14:18:00Z
 | `abbreviation` | TEXT    | Short label (e.g. `CRY`), 2–6 chars, server-uppercased. Globally unique — enforced by `uq_category_abbreviation`. |
 | `description`  | TEXT    | Optional description.                                                         |
 | `icon_path`    | TEXT    | Default icon URL (e.g. `/uploads/icons/CRY.png`).                             |
-| `created_at`   | TEXT    | ISO 8601 timestamp the row was created (added by `AddCategoryTimestampsAndUniqueAbbrev1700000000200`). |
-| `updated_at`   | TEXT    | ISO 8601 timestamp the row was last updated (added by the same migration; bumped on `PUT /api/v1/admin/categories/:id`). |
+| `created_at`   | TEXT    | ISO 8601 timestamp the row was created. Declared in the initial `InitSchema1700000000000` migration (defaulting to `strftime('%Y-%m-%dT%H:%M:%fZ','now')`); the `AddCategoryTimestampsAndUniqueAbbrev1700000000200` migration adds it as a no-op for older pre-existing databases. |
+| `updated_at`   | TEXT    | ISO 8601 timestamp the row was last updated (bumped on `PUT /api/v1/admin/categories/:id`). Same provenance as `created_at`. |
 
 System rows are seeded by the
 `UpdateSystemCategoryKeys1700000000300` migration so the canonical
diff --git a/docs/database/schema.md b/docs/database/schema.md
index a9ae386..a2f2f07 100644
--- a/docs/database/schema.md
+++ b/docs/database/schema.md
@@ -3,7 +3,7 @@ type: database
 title: Database Schema Overview
 description: SQLite (better-sqlite3) schema for HIPCTF: tables, relationships, indexes, and WAL journal mode.
 tags: [database, sqlite, typeorm, schema]
-timestamp: 2026-07-21T14:18:00Z
+timestamp: 2026-07-22T14:50:25Z
 ---
 
 # Overview
@@ -17,6 +17,12 @@ The schema is created by a single migration
 (`backend/src/database/migrations/1700000000000-InitSchema.ts`) and seeded
 by a second migration
 (`backend/src/database/migrations/1700000000100-SeedSystemData.ts`).
+The initial migration declares every column used by the entities
+(including `category.created_at` and `category.updated_at`), so the
+later `AddCategoryTimestampsAndUniqueAbbrev1700000000200` and
+`UpdateSystemCategoryKeys1700000000300` migrations only patch legacy
+databases that pre-date those columns and reseed the canonical system
+rows.
 
 # Tables
 
diff --git a/docs/guides/admin-general-settings.md b/docs/guides/admin-general-settings.md
index 02f081d..df3f3b3 100644
--- a/docs/guides/admin-general-settings.md
+++ b/docs/guides/admin-general-settings.md
@@ -3,7 +3,7 @@ type: guide
 title: Admin — General Settings
 description: How an admin edits required platform-wide settings, including the validated event window, from the /admin/general page.
 tags: [guide, admin, settings, general, tester, datetime, validation]
-timestamp: 2026-07-22T14:24:08Z
+timestamp: 2026-07-22T14:50:25Z
 ---
 
 # When this view is available
@@ -17,7 +17,7 @@ by navigating directly to the URL.
 |------------------|----------------------------------------------------------------------------|------------------------------------------------|
 | Client route     | `frontend/src/app/app.routes.ts`                                           | `/admin/general` child of `adminGuard`.        |
 | Client component | `frontend/src/app/features/admin/general.component.ts`                     | `AdminGeneralComponent.ngOnInit` fetches settings + themes. |
-| Client predicate | `frontend/src/app/features/admin/general.pure.ts` (`deriveEventState`, `pageTitleError`, `pageTitleMessage`) | Pure helpers for event-state derivation and Page-title error/message mapping. |
+| Client predicate | `frontend/src/app/features/admin/general.pure.ts` (`deriveEventState`, `pageTitleError`, `pageTitleMessage`, `eventEndFieldMessage`) | Pure helpers for event-state derivation, Page-title error/message mapping, and the merged Event End field message (per-field `invalidDatetime` + cross-field `endBeforeStart`). |
 | Server route     | `backend/src/modules/admin/admin-general.controller.ts`                    | `GET/PUT /api/v1/admin/general/settings` + `GET /api/v1/admin/general/themes`. |
 
 # How to access (tester steps)
@@ -43,7 +43,7 @@ The page is a single reactive form with these controls (every
 | Logo upload status     | `general-logo-uploading` / `general-logo-error` / `general-logo-current` | — | Inline status text under the file picker. |
 | Global theme           | `general-themeKey`        | `themeKey`              | `<select>` populated from `/themes`. Value is one of `THEME_IDS`. |
 | Event start (UTC)      | `general-eventStart`      | `eventStartUtc`         | Required valid ISO-8601 datetime. Empty or malformed input renders `general-eventStart-error` and disables Save. |
-| Event end (UTC)        | `general-eventEnd`        | `eventEndUtc`           | Required valid ISO-8601 datetime. Empty or malformed input renders `general-eventEnd-error`; it must also be strictly after Event start (`general-endBeforeStart`). |
+| Event end (UTC)        | `general-eventEnd`        | `eventEndUtc`           | Required valid ISO-8601 datetime. Empty or malformed input renders `general-eventEnd-error`; it must also be strictly after Event start — when it is not, the same `general-eventEnd-error` region displays "Event end must be after event start." |
 | Default challenge IP   | `general-defaultIp`       | `defaultChallengeIp`    | Required, max 255 chars. |
 | Enable registrations   | `general-registrations`   | `registrationsEnabled`  | Boolean checkbox. When `false`, the public register endpoint returns `REGISTRATIONS_DISABLED`. |
 | Welcome description    | `general-welcome`         | `welcomeMarkdown`       | Multi-line textarea; a live preview is rendered into `general-welcome-preview`. |
@@ -71,9 +71,9 @@ The page is a single reactive form with these controls (every
   * `start <= now < end` → `RUNNING`
   * `now >= end` → `STOPPED`
 * **End-before-start validation:** if the user picks an end that is not
-  strictly after the start, the form becomes invalid and
-  `general-endBeforeStart` appears under the end input. Save remains
-  disabled.
+  strictly after the start, the form becomes invalid and the
+  `general-eventEnd-error` region under the end input renders
+  "Event end must be after event start." Save remains disabled.
 * **Per-field datetime validation:** clearing a field or supplying a value
   that cannot be parsed as an ISO-8601 datetime makes that control invalid.
   The affected input receives `aria-invalid="true"`, references its inline
@@ -136,6 +136,16 @@ two pure helpers exported from
 * `datetimeMessage(fieldLabel, value, controlErrors)` — renders the
   human-readable message `"<Field> must be a valid ISO-8601 datetime."`
   when `invalidDatetime` is set or when the raw value is unparseable.
+* `eventEndFieldMessage(controlErrors, crossFieldErrors)` — returns the
+  canonical message for the Event End field's own error region. It
+  prefers the per-field ISO message
+  (`"Event end must be a valid ISO-8601 datetime."`) when
+  `controlErrors?.['invalidDatetime']` is set, otherwise it surfaces the
+  cross-field `endBeforeStart` message
+  (`"Event end must be after event start."`), otherwise `null`. The
+  component reads this helper through the `eventEndFieldMessageText`
+  computed signal so both error kinds render inside the single
+  `general-eventEnd-error` element.
 
 The component wires both controls (`eventStartUtc`, `eventEndUtc`) with
 this validator and keeps three local `signal`s per field — `Value`,
@@ -160,11 +170,14 @@ The error is shown only when the control is both `touched || dirty`
 AND `invalid`, so the inputs do not flash errors on initial load. After
 a successful Save, both controls are reset to untouched/pristine via
 `resetTouchedState()` and their `TouchedOrDirty` signals are cleared.
-The cross-field `endBeforeStart` error (`general-endBeforeStart`) is
-emitted by the form-level validator whenever both valid timestamps are
-present and end is not strictly after start. The Event end input also
-receives `aria-invalid="true"`, references both possible error elements,
-and exposes `Event end must be after event start.` as its title.
+The cross-field `endBeforeStart` error is emitted by the form-level
+validator whenever both valid timestamps are present and end is not
+strictly after start. The Event end input receives `aria-invalid="true"`,
+references `general-eventEnd-error` via `aria-describedby`, and exposes
+`Event end must be after event start.` as its title — the message itself
+is rendered inside the per-field error region
+(`data-testid="general-eventEnd-error"`) by the
+`eventEndFieldMessage` helper.
 
 # Visual elements
 
@@ -175,9 +188,8 @@ and exposes `Event end must be after event start.` as its title.
 | Load error                    | `[data-testid="general-error"]`                     |
 | Form                          | `[data-testid="general-form"]`                      |
 | Welcome preview               | `[data-testid="general-welcome-preview"]`           |
-| End-before-start message      | `[data-testid="general-endBeforeStart"]`            |
 | Event start inline error      | `[data-testid="general-eventStart-error"]`          |
-| Event end inline error        | `[data-testid="general-eventEnd-error"]`            |
+| Event end inline error        | `[data-testid="general-eventEnd-error"]` (renders both the per-field `invalidDatetime` message and the cross-field `endBeforeStart` "Event end must be after event start." message) |
 | Page-title inline error       | `[data-testid="general-pageTitle-error"]`           |
 
 # Architecture map
diff --git a/docs/index.md b/docs/index.md
index e8beaf4..ac6c30f 100644
--- a/docs/index.md
+++ b/docs/index.md
@@ -11,7 +11,7 @@ scoreboard, an event window with a public countdown, theming, and admin
 controls.
 
 The docs below are organized by purpose so agents can pull just the slice
-they need. Last regenerated 2026-07-22T14:24:08Z.
+they need. Last regenerated 2026-07-22T14:50:25Z.
 
 # Architecture