diff --git a/documentation/migration-guides/migration-4.3.rst b/documentation/migration-guides/migration-4.3.rst
index 278697545e..9f8fe34ca3 100644
--- a/documentation/migration-guides/migration-4.3.rst
+++ b/documentation/migration-guides/migration-4.3.rst
@@ -130,6 +130,9 @@ The following variables have been removed:
 -  ``PERLARCH``
 -  ``PERLVERSION``
 -  ``QEMU_USE_SLIRP``
+-  ``SERIAL_CONSOLES_CHECK``, which is no longer necessary because all
+   consoles listed in :term:`SERIAL_CONSOLES` are checked for their existence
+   before a ``getty`` is started.
 
 .. _migration-4.3-removed-recipes:
 
diff --git a/documentation/migration-guides/release-notes-4.3.rst b/documentation/migration-guides/release-notes-4.3.rst
index 4da23837a2..717c4e39d5 100644
--- a/documentation/migration-guides/release-notes-4.3.rst
+++ b/documentation/migration-guides/release-notes-4.3.rst
@@ -92,7 +92,8 @@ New Features / Enhancements in 4.3
 
    -  `ttyrun <https://github.com/ibm-s390-linux/s390-tools>`__, starts
       ``getty`` programs only when a terminal exists, preventing respawns
-      through the ``init`` program.
+      through the ``init`` program. This allowed to remove the
+      ``SERIAL_CONSOLES_CHECK`` variable.
 
 -  New classes: