Clarify 2.3.0 kubernetes min version is about library not cluster
diff --git a/README.md b/README.md
index 6f5830e68b211..01eab7b755979 100644
--- a/README.md
+++ b/README.md
@@ -85,15 +85,15 @@ Airflow is not a streaming solution, but it is often used to process real-time d
 
 Apache Airflow is tested with:
 
-|                     | Main version (dev)      | Stable version (2.3.0)   |
-|---------------------|-------------------------|--------------------------|
-| Python              | 3.7, 3.8, 3.9, 3.10     | 3.6, 3.7, 3.8, 3.9       |
-| Platform            | AMD64/ARM64(\*)         | AMD64                    |
-| Kubernetes          | 1.20, 1.21, 1.22, 1.23  | 1.18, 1.19, 1.20         |
-| PostgreSQL          | 10, 11, 12, 13          | 9.6, 10, 11, 12, 13      |
-| MySQL               | 5.7, 8                  | 5.7, 8                   |
-| SQLite              | 3.15.0+                 | 3.15.0+                  |
-| MSSQL               | 2017(\*), 2019 (\*)     |                          |
+|                     | Main version (dev)      | Stable version (2.3.0)  |
+|---------------------|-------------------------|-------------------------|
+| Python              | 3.7, 3.8, 3.9, 3.10     | 3.6, 3.7, 3.8, 3.9      |
+| Platform            | AMD64/ARM64(\*)         | AMD64                   |
+| Kubernetes          | 1.20, 1.21, 1.22, 1.23  | 1.20, 1.21, 1.22, 1.23  |
+| PostgreSQL          | 10, 11, 12, 13          | 9.6, 10, 11, 12, 13     |
+| MySQL               | 5.7, 8                  | 5.7, 8                  |
+| SQLite              | 3.15.0+                 | 3.15.0+                 |
+| MSSQL               | 2017(\*), 2019 (\*)     |                         |
 
 \* Experimental
 
diff --git a/RELEASE_NOTES.rst b/RELEASE_NOTES.rst
index a13e8e3ef0a7e..15ac6c1b0a389 100644
--- a/RELEASE_NOTES.rst
+++ b/RELEASE_NOTES.rst
@@ -41,8 +41,13 @@ Previously, a task’s log is dynamically rendered from the ``[core] log_filenam
 
 A new ``log_template`` table is introduced to solve this problem. This table is synchronized with the aforementioned config values every time Airflow starts, and a new field ``log_template_id`` is added to every DAG run to point to the format used by tasks (``NULL`` indicates the first ever entry for compatibility).
 
-Minimum kubernetes version bumped from ``3.0.0`` to ``21.7.0`` (#20759)
-"""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""
+Minimum kubernetes library version bumped from ``3.0.0`` to ``21.7.0`` (#20759)
+"""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""
+
+.. note::
+
+   This is only about changing the ``kubernetes`` library, not the Kubernetes cluster. Airflow support for
+   Kubernetes version is described in `Installation prerequisites <https://airflow.apache.org/docs/apache-airflow/stable/installation/prerequisites.html>`_.
 
 No change in behavior is expected.  This was necessary in order to take advantage of a `bugfix <https://github.com/kubernetes-client/python-base/commit/70b78cd8488068c014b6d762a0c8d358273865b4>`_ concerning refreshing of Kubernetes API tokens with EKS, which enabled the removal of some `workaround code <https://github.com/apache/airflow/pull/20759>`_.
 

It was not clear from the release notes that the minimum version
of the kubernetes was about the library rather than cluster version.

Also README was not updated with min versions of Kubernetes cluster
for 2.3.0 version.

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