Update Microsoft Exchange Online SMTP basic auth deprecation date in GHES release notes (#57382)

Co-authored-by: hubwriter <hubwriter@github.com>

data/release-notes/enterprise-server/3-14/12.yml

@@ -53,7 +53,7 @@ sections:
       Merging a pull request using the "Rebase and merge" option is now limited to 100 commits. If you have a pull request with more than 100 commits, you can create a merge commit, or squash and merge, or split the commits into multiple pull requests.
   closing_down:
     - |
-      Microsoft Exchange Online is retiring SMTP basic authentication in September 2025. If your GitHub Enterprise Server instance uses this method to send email, delivery may fail after the retirement date. Microsoft recommends switching to a supported alternative. As another option, you may consider using an SMTP OAuth proxy such as [email-oauth2-proxy](https://github.com/simonrob/email-oauth2-proxy), though this is not officially supported. For details and configuration guidance, see the [Microsoft announcement](https://techcommunity.microsoft.com/blog/exchange/exchange-online-to-retire-basic-auth-for-client-submission-smtp-auth/4114750) and the proxy’s [documentation](https://github.com/simonrob/email-oauth2-proxy/blob/main/emailproxy.config).
+      Microsoft Exchange Online is retiring SMTP basic authentication during March-April 2026. If your GitHub Enterprise Server instance uses this method to send email, delivery may fail after the retirement date. Microsoft recommends switching to a supported alternative. As another option, you may consider using an SMTP OAuth proxy such as [email-oauth2-proxy](https://github.com/simonrob/email-oauth2-proxy), though this is not officially supported. For details and configuration guidance, see the [Microsoft announcement](https://techcommunity.microsoft.com/blog/exchange/exchange-online-to-retire-basic-auth-for-client-submission-smtp-auth/4114750) and the proxy’s [documentation](https://github.com/simonrob/email-oauth2-proxy/blob/main/emailproxy.config). [Updated: 2025-09-03]
   known_issues:
     - |
       During the validation phase of a configuration run, a `No such object` error may occur for the Notebook and Viewscreen services. This error can be ignored as the services should still correctly start.

data/release-notes/enterprise-server/3-15/7.yml

@@ -63,7 +63,7 @@ sections:
       Merging a pull request using the "Rebase and merge" option is now limited to 100 commits. If you have a pull request with more than 100 commits, you can create a merge commit, or squash and merge, or split the commits into multiple pull requests.
   closing_down:
     - |
-      Microsoft Exchange Online is retiring SMTP basic authentication in September 2025. If your GitHub Enterprise Server instance uses this method to send email, delivery may fail after the retirement date. Microsoft recommends switching to a supported alternative. As another option, you may consider using an SMTP OAuth proxy such as [email-oauth2-proxy](https://github.com/simonrob/email-oauth2-proxy), though this is not officially supported. For details and configuration guidance, see the [Microsoft announcement](https://techcommunity.microsoft.com/blog/exchange/exchange-online-to-retire-basic-auth-for-client-submission-smtp-auth/4114750) and the proxy’s [documentation](https://github.com/simonrob/email-oauth2-proxy/blob/main/emailproxy.config).
+      Microsoft Exchange Online is retiring SMTP basic authentication during March-April 2026. If your GitHub Enterprise Server instance uses this method to send email, delivery may fail after the retirement date. Microsoft recommends switching to a supported alternative. As another option, you may consider using an SMTP OAuth proxy such as [email-oauth2-proxy](https://github.com/simonrob/email-oauth2-proxy), though this is not officially supported. For details and configuration guidance, see the [Microsoft announcement](https://techcommunity.microsoft.com/blog/exchange/exchange-online-to-retire-basic-auth-for-client-submission-smtp-auth/4114750) and the proxy’s [documentation](https://github.com/simonrob/email-oauth2-proxy/blob/main/emailproxy.config). [Updated: 2025-09-03]
   known_issues:
     - |
       During the validation phase of a configuration run, a `No such object` error may occur for the Notebook and Viewscreen services. This error can be ignored as the services should still correctly start.

data/release-notes/enterprise-server/3-16/3.yml

@@ -57,7 +57,7 @@ sections:
       Merging a pull request using the "Rebase and merge" option is now limited to 100 commits. If you have a pull request with more than 100 commits, you can create a merge commit, or squash and merge, or split the commits into multiple pull requests.
   closing_down:
     - |
-      Microsoft Exchange Online is retiring SMTP basic authentication in September 2025. If your GitHub Enterprise Server instance uses this method to send email, delivery may fail after the retirement date. Microsoft recommends switching to a supported alternative. As another option, you may consider using an SMTP OAuth proxy such as [email-oauth2-proxy](https://github.com/simonrob/email-oauth2-proxy), though this is not officially supported. For details and configuration guidance, see the [Microsoft announcement](https://techcommunity.microsoft.com/blog/exchange/exchange-online-to-retire-basic-auth-for-client-submission-smtp-auth/4114750) and the proxy’s [documentation](https://github.com/simonrob/email-oauth2-proxy/blob/main/emailproxy.config).
+      Microsoft Exchange Online is retiring SMTP basic authentication during March-April 2026. If your GitHub Enterprise Server instance uses this method to send email, delivery may fail after the retirement date. Microsoft recommends switching to a supported alternative. As another option, you may consider using an SMTP OAuth proxy such as [email-oauth2-proxy](https://github.com/simonrob/email-oauth2-proxy), though this is not officially supported. For details and configuration guidance, see the [Microsoft announcement](https://techcommunity.microsoft.com/blog/exchange/exchange-online-to-retire-basic-auth-for-client-submission-smtp-auth/4114750) and the proxy’s [documentation](https://github.com/simonrob/email-oauth2-proxy/blob/main/emailproxy.config). [Updated: 2025-09-03]
   known_issues:
     - |
       Customers operating at high scale or near capacity may experience unexpected performance degradation, such as slow response times, background job queue spikes, elevated CPU usage, and increased MySQL load. Consider upgrading to 3.16 with caution. [Updated: 2025-07-28]

data/release-notes/enterprise-server/3-17/0-rc1.yml

@@ -212,7 +212,7 @@ sections:
     - |
       In GitHub Enterprise Server 3.20, GitHub will retire the security manager API in favor of the organization roles API. See the [GitHub Blog](https://github.blog/changelog/2024-12-10-notice-of-breaking-changes-security-manager-rest-api-will-be-retired-and-replaced-with-the-organization-roles-rest-api/).
     - |
-      Microsoft Exchange Online is retiring SMTP basic authentication in September 2025. If your GitHub Enterprise Server instance uses this method to send email, delivery may fail after the retirement date. Microsoft recommends switching to a supported alternative. As another option, you may consider using an SMTP OAuth proxy such as [email-oauth2-proxy](https://github.com/simonrob/email-oauth2-proxy), though this is not officially supported. For details and configuration guidance, see the [Microsoft announcement](https://techcommunity.microsoft.com/blog/exchange/exchange-online-to-retire-basic-auth-for-client-submission-smtp-auth/4114750) and the proxy’s [documentation](https://github.com/simonrob/email-oauth2-proxy/blob/main/emailproxy.config).
+      Microsoft Exchange Online is retiring SMTP basic authentication during March-April 2026. If your GitHub Enterprise Server instance uses this method to send email, delivery may fail after the retirement date. Microsoft recommends switching to a supported alternative. As another option, you may consider using an SMTP OAuth proxy such as [email-oauth2-proxy](https://github.com/simonrob/email-oauth2-proxy), though this is not officially supported. For details and configuration guidance, see the [Microsoft announcement](https://techcommunity.microsoft.com/blog/exchange/exchange-online-to-retire-basic-auth-for-client-submission-smtp-auth/4114750) and the proxy’s [documentation](https://github.com/simonrob/email-oauth2-proxy/blob/main/emailproxy.config). [Updated: 2025-09-03]
 
   retired:
     # https://github.com/github/releases/issues/5433

data/release-notes/enterprise-server/3-17/0.yml

@@ -221,7 +221,7 @@ sections:
     - |
       In GitHub Enterprise Server 3.20, GitHub will retire the security manager API in favor of the organization roles API. See the [GitHub Blog](https://github.blog/changelog/2024-12-10-notice-of-breaking-changes-security-manager-rest-api-will-be-retired-and-replaced-with-the-organization-roles-rest-api/).
     - |
-      Microsoft Exchange Online is retiring SMTP basic authentication in September 2025. If your GitHub Enterprise Server instance uses this method to send email, delivery may fail after the retirement date. Microsoft recommends switching to a supported alternative. As another option, you may consider using an SMTP OAuth proxy such as [email-oauth2-proxy](https://github.com/simonrob/email-oauth2-proxy), though this is not officially supported. For details and configuration guidance, see the [Microsoft announcement](https://techcommunity.microsoft.com/blog/exchange/exchange-online-to-retire-basic-auth-for-client-submission-smtp-auth/4114750) and the proxy’s [documentation](https://github.com/simonrob/email-oauth2-proxy/blob/main/emailproxy.config).
+      Microsoft Exchange Online is retiring SMTP basic authentication during March-April 2026. If your GitHub Enterprise Server instance uses this method to send email, delivery may fail after the retirement date. Microsoft recommends switching to a supported alternative. As another option, you may consider using an SMTP OAuth proxy such as [email-oauth2-proxy](https://github.com/simonrob/email-oauth2-proxy), though this is not officially supported. For details and configuration guidance, see the [Microsoft announcement](https://techcommunity.microsoft.com/blog/exchange/exchange-online-to-retire-basic-auth-for-client-submission-smtp-auth/4114750) and the proxy’s [documentation](https://github.com/simonrob/email-oauth2-proxy/blob/main/emailproxy.config). [Updated: 2025-09-03]
 
   retired:
     # https://github.com/github/releases/issues/5433