Merge pull request ckeditor#14213 from ckeditor/ci/2975

Docs: Added information about CKE4 EOL to CKE4 migration sections. Closes cksource/ckeditor5-internal#2975.

docs/installation/migration-from-ckeditor-4.md

@@ -19,6 +19,8 @@ In the other tutorials from this section you could learn about installing, confi
 
 When compared to its predecessor, CKEditor 5 should be considered **a totally new editor**.
 
+**CKEditor 4 reaches its End of Life (EOL) in June 2023.** From then on, it will receive no more updates, new features, bug fixes, and most importantly, security patches.
+
 To support you in migration to CKEditor 5, we have created an entire documentation section that covers various aspects of the migration process.
 
 Read more about:

docs/updating/migration-from-ckeditor-4.md

@@ -9,6 +9,14 @@ modified_at: 2023-03-21
 
 # Migration from CKEditor 4
 
+This section of the documentation explains how to migrate to CKEditor 5.
+
+<info-box hint>
+	<strong>CKEditor 4 reaches its End of Life (EOL) in June 2023</strong>. From then on, it will receive no more updates, new features, bug fixes, and most importantly, security patches.
+
+	If you have an active CKEditor 4 subscription and need help, you can contact [our support team](https://ckeditor.com/contact/). If you are not ready to migrate yet, for a limited time we are offering a paid <strong>Extended Support Model</strong> that will protect you against security vulnerabilities and/or breaking third-party API changes.
+</info-box>
+
 When compared to its predecessor, CKEditor 5 should be considered **a totally new editor**. Every single aspect of it was redesigned &mdash; from installation, to integration, to features, to its data model, and finally to its API.
 
 There is no automatic solution for migrating. This section summarizes the most important aspects you need to consider before you proceed with moving to CKEditor 5.
@@ -212,3 +220,5 @@ CKEditor 5 is a great, modern editing framework so migrating is a fantastic oppo
 If you are missing any particular features or settings, feel free to {@link support/reporting-issues#reporting-issues-2 report an issue}. Search the [issues section in the repository](https://github.com/ckeditor/ckeditor5/issues) first, as the feature you are after may have already been reported &mdash; you can support it by upvoting the issue with &nbsp;👍. Please be as precise as possible, explaining the exact use case, the context where the editor is used, and the expected behavior.
 
 The {@link updating/ckeditor4-troubleshooting Troubleshooting migration from CKEditor 4} article answers some frequently asked questions about the migration.
+
+[Contact the support team](https://ckeditor.com/contact/) if you want to learn more about licensing or the [Extended Support Model](https://ckeditor.com/ckeditor-4-support/).