diff --git a/docs/en/04_Changelogs/4.2.0.md b/docs/en/04_Changelogs/4.2.0.md
index 638d69761..a021010ae 100644
--- a/docs/en/04_Changelogs/4.2.0.md
+++ b/docs/en/04_Changelogs/4.2.0.md
@@ -134,3 +134,11 @@ and are replaced by the `SiteTreeLink` and `FileLink` many_many through joining
 Code which relies on raw SQL queries to these tables will need to be updated.
 
 `SiteTreeFileExtension` is deprecated, and has it's functionality baked directly into `File` dataobject.
+
+### New upgrader command
+The SilverStripe upgrader tool can now be used to convert your `_ss_environment.php` file to an equivalent `.env` file when migrating a SilverStripe 3 project to SilverStripe 4.
+
+```
+cd ~/my-project-root
+upgrade-code environment --write
+```