Update docs for Copilot Metrics API deprecation (#60351)

Co-authored-by: Ben Ahmady <32935794+subatoi@users.noreply.github.com>

Author: a1exmozz

content/copilot/concepts/copilot-usage-metrics/copilot-metrics.md

@@ -55,7 +55,6 @@ The following API resources expose {% data variables.product.prodname_copilot_sh
 | --- | --- | --- |
 | [AUTOTITLE](/rest/copilot/copilot-usage-metrics) | Advanced enterprise-, organization-, and user-level event telemetry | Provides unified telemetry across completions, chat, and agent modes. Includes usage and lines of code metrics across all IDE modes, languages, and models. Supports detailed breakdowns by feature, IDE, language, model, and user, and is the primary API resource being actively developed and maintained. |
 | [AUTOTITLE](/rest/copilot/copilot-user-management) | License and seat assignment | Lists assigned {% data variables.product.prodname_copilot_short %} seats for an organization or enterprise, including license state, user association, and `last_activity_at`. This API resource is the source of truth for license and seat information. |
-| [AUTOTITLE](/rest/copilot/copilot-metrics) | Enterprise-, organization-, and team-level usage metrics | Provides aggregated usage data for {% data variables.product.prodname_copilot_short %} features on {% data variables.product.prodname_dotcom_the_website %} (such as pull request summaries) and some IDE-based completions and chat. Does not include Agent or Edit mode telemetry. Offers enterprise-wide and per-feature breakdowns by IDE and language. Does not include individual-level data. |
 
 ## How are metrics attributed across organizations?
 

content/copilot/reference/policy-conflicts.md

@@ -34,7 +34,7 @@ Feature, model, and privacy settings for users are set according to the **least
 
 | Policy | Availability matches | More information |
 | :---- | :---- | :---- |
-| {% data variables.product.prodname_copilot_short %} Metrics API | Most restrictive organization | [AUTOTITLE](/rest/copilot/copilot-metrics) |
+| {% data variables.product.prodname_copilot_short %} Metrics API | Most restrictive organization | {% ifversion ghec %}[AUTOTITLE](/rest/copilot/copilot-usage-metrics){% else %}Not applicable{% endif %} |
 | Suggestions matching public code (privacy policy) | Most restrictive organization | [AUTOTITLE](/copilot/concepts/completions/code-suggestions) |
 | Allow members without a {% data variables.product.prodname_copilot_short %} license to use {% data variables.copilot.copilot_code-review_short %} in {% data variables.product.prodname_dotcom_the_website %} | Most restrictive organization | [AUTOTITLE](/copilot/responsible-use/code-review) |
 | {% data variables.product.prodname_copilot_short %} can search the web | Least restrictive organization | [AUTOTITLE](/copilot/responsible-use/chat-in-github#leveraging-a-web-search-to-answer-a-question) |

data/reusables/copilot/copilot-metrics-closing-down.md

@@ -1,2 +1,2 @@
 >[!WARNING]
-> These {% data variables.product.prodname_copilot_short %} metrics endpoints will be {% data variables.release-phases.closing_down %} on April 2, 2026. We recommend using the **{% data variables.product.prodname_copilot_short %} usage metrics** endpoints instead, which provide more depth and flexibility. For more details, see [{% data variables.product.prodname_blog %}](https://github.blog/changelog/2026-01-29-closing-down-notice-of-legacy-copilot-metrics-apis/).
+> These {% data variables.product.prodname_copilot_short %} metrics endpoints were closed down on April 2, 2026. Use the **{% data variables.product.prodname_copilot_short %} usage metrics** endpoints instead, which provide more depth and flexibility. For more details, see [{% data variables.product.prodname_blog %}](https://github.blog/changelog/2026-01-29-closing-down-notice-of-legacy-copilot-metrics-apis/).