diff --git a/docs/src/customization.md b/docs/src/customization.md
index f0b96540a46b8e4f4dda637386c31f738a5e7d17..c47c891123e1e60e9e75e8c8e3158e066226fa47 100644
--- a/docs/src/customization.md
+++ b/docs/src/customization.md
@@ -23,15 +23,17 @@ file. A minimal example for a BSP based on `meta-ked-bsp` looks like this:
 
 ```yaml title="custom.yaml"
 header:
-  version: 12
+  version: 15
   includes:
     - repo: meta-ked-bsp
       file: kas/inc/imx.yml
+    - repo: meta-ked-bsp
+      file: kas/series/kirkstone.yml
 
 repos:
   meta-ked-bsp:
     url: https://git.kontron-electronics.de/sw/ked/meta-ked-bsp.git
-    refspec: 6.0.0
+    branch: main
     path: layers/meta-ked-bsp
 
 machine: kontron-mx8mm
@@ -70,7 +72,7 @@ edit our `kas` configuration.
  repos:
    meta-ked-bsp:
      url: https://git.kontron-electronics.de/sw/ked/meta-ked-bsp.git
-     refspec: 6.0.0
+     branch: main
      path: layers/meta-ked-bsp
 +  meta-custom:
 +    layers:
@@ -80,3 +82,9 @@ edit our `kas` configuration.
 Now with your custom layer setup you can add your customizations such as machine
 or distro configs, image recipes or any other Yocto/OE metadata to the new layer
 in `layers/meta-custom`.
+
+!!! info "Pinning References"
+    We recommend that you use `kas` lockfiles for pinning the references of any
+    external layers (including `meta-ked-bsp`) to a fixed state. Please see [the
+    documentation](https://kas.readthedocs.io/en/latest/userguide/project-configuration.html#working-with-lockfiles)
+    for further information.