Add deprecation notes to abstract

Author: zooba

peps/pep-0773.rst

@@ -31,6 +31,12 @@ having global ``python3.x`` commands by adding an extra entry to their ``PATH``
 environment variable. We recommend starting with the "How to teach this" section
 for the most concise high-level overview of the features.
 
+The existing ``.exe`` installer and ``py`` launcher will be deprecated and no
+longer released from two years after this PEP is accepted. The existing
+embeddable distro will no longer be listed as a download, but will be available
+through the install manager. The Windows Store app will be immediately replaced
+with the install manager.
+
 Reader's Note
 -------------