diff --git a/core/modules/migrate_drupal/src/MigrationState.php b/core/modules/migrate_drupal/src/MigrationState.php
index d191511075..f15b9e9e9e 100644
--- a/core/modules/migrate_drupal/src/MigrationState.php
+++ b/core/modules/migrate_drupal/src/MigrationState.php
@@ -9,15 +9,15 @@
  *
  * Deciding the upgrade state of a source module is a complicated task. A
  * destination module is not limited in any way to the source modules or the
- * current major version destination modules it is providing migrations for. We see this in
- * core where the Drupal 6 Menu module is upgraded by having migrations in three
- * Drupal 8 modules; menu_link_content, menu_ui and system. And it is only when
- * all those migrations are complete, in all three modules, that the Drupal 6
- * Menu module should be listed as will be upgraded. If any one of the
- * migrations are not finished then it should be listed as will not be upgraded.
- * There is not enough information in the existing system to determine if a
- * source module has a complete upgrade path or not or even if it does not need
- * an upgrade path.
+ * current major version destination modules it is providing migrations for. We
+ * see this in core where the Drupal 6 Menu module is upgraded by having
+ * migrations in three Drupal 8 modules; menu_link_content, menu_ui and system.
+ * And it is only when all those migrations are complete, in all three modules,
+ * that the Drupal 6 Menu module should be listed as will be upgraded. If any
+ * one of the migrations are not finished then it should be listed as will not
+ * be upgraded. There is not enough information in the existing system to
+ * determine if a source module has a complete upgrade path or not or even if it
+ * does not need an upgrade path.
  *
  * The solution is for every destination module that is the successor to a
  * module built for a legacy Drupal version to declare the state of the upgrade
@@ -44,12 +44,12 @@
  * # for the migrations that this module provides and are complete.
  * finished:
  *   # One or more Drupal legacy version number mappings (i.e. 6 and/or 7).
- *   <legacy_version>:
+ *   6:
  *     # A mapping of legacy module machine names to a comma separated list of
  *     # destination module machine names.
  *     <source_module_1>: <destination_module_1>
  *     <source_module_2>: <destination_module_1>, <destination_module_2>
- *   <another_legacy_version>:
+ *   7:
  *     <source_module_1>: <destination_module_1>
  *     <source_module_2>: <destination_module_1>, <destination_module_2>
  * # (optional) List of the source_module/destination_module pairs that this
@@ -57,7 +57,7 @@
  * # exist.
  * not_finished:
  *   # One or more Drupal legacy version number mappings (i.e. 6 and/or 7).
- *   <legacy_version>:
+ *   6:
  *     # A mapping of legacy module machine names to a comma separated list of
  *     # destination module machine names to define this migration path.
  *     <source_module_1>: <destination_module_1>